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diff --git a/node_modules/dependency-graph/lib/dep_graph.js b/node_modules/dependency-graph/lib/dep_graph.js
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+/**
+ * A simple dependency graph
+ */
+
+/**
+ * Helper for creating a Topological Sort using Depth-First-Search on a set of edges.
+ *
+ * Detects cycles and throws an Error if one is detected (unless the "circular"
+ * parameter is "true" in which case it ignores them).
+ *
+ * @param edges The set of edges to DFS through
+ * @param leavesOnly Whether to only return "leaf" nodes (ones who have no edges)
+ * @param result An array in which the results will be populated
+ * @param circular A boolean to allow circular dependencies
+ */
+function createDFS(edges, leavesOnly, result, circular) {
+  var visited = {};
+  return function (start) {
+    if (visited[start]) {
+      return;
+    }
+    var inCurrentPath = {};
+    var currentPath = [];
+    var todo = []; // used as a stack
+    todo.push({ node: start, processed: false });
+    while (todo.length > 0) {
+      var current = todo[todo.length - 1]; // peek at the todo stack
+      var processed = current.processed;
+      var node = current.node;
+      if (!processed) {
+        // Haven't visited edges yet (visiting phase)
+        if (visited[node]) {
+          todo.pop();
+          continue;
+        } else if (inCurrentPath[node]) {
+          // It's not a DAG
+          if (circular) {
+            todo.pop();
+            // If we're tolerating cycles, don't revisit the node
+            continue;
+          }
+          currentPath.push(node);
+          throw new DepGraphCycleError(currentPath);
+        }
+
+        inCurrentPath[node] = true;
+        currentPath.push(node);
+        var nodeEdges = edges[node];
+        // (push edges onto the todo stack in reverse order to be order-compatible with the old DFS implementation)
+        for (var i = nodeEdges.length - 1; i >= 0; i--) {
+          todo.push({ node: nodeEdges[i], processed: false });
+        }
+        current.processed = true;
+      } else {
+        // Have visited edges (stack unrolling phase)
+        todo.pop();
+        currentPath.pop();
+        inCurrentPath[node] = false;
+        visited[node] = true;
+        if (!leavesOnly || edges[node].length === 0) {
+          result.push(node);
+        }
+      }
+    }
+  };
+}
+
+/**
+ * Simple Dependency Graph
+ */
+var DepGraph = (exports.DepGraph = function DepGraph(opts) {
+  this.nodes = {}; // Node -> Node/Data (treated like a Set)
+  this.outgoingEdges = {}; // Node -> [Dependency Node]
+  this.incomingEdges = {}; // Node -> [Dependant Node]
+  this.circular = opts && !!opts.circular; // Allows circular deps
+});
+DepGraph.prototype = {
+  /**
+   * The number of nodes in the graph.
+   */
+  size: function () {
+    return Object.keys(this.nodes).length;
+  },
+  /**
+   * Add a node to the dependency graph. If a node already exists, this method will do nothing.
+   */
+  addNode: function (node, data) {
+    if (!this.hasNode(node)) {
+      // Checking the arguments length allows the user to add a node with undefined data
+      if (arguments.length === 2) {
+        this.nodes[node] = data;
+      } else {
+        this.nodes[node] = node;
+      }
+      this.outgoingEdges[node] = [];
+      this.incomingEdges[node] = [];
+    }
+  },
+  /**
+   * Remove a node from the dependency graph. If a node does not exist, this method will do nothing.
+   */
+  removeNode: function (node) {
+    if (this.hasNode(node)) {
+      delete this.nodes[node];
+      delete this.outgoingEdges[node];
+      delete this.incomingEdges[node];
+      [this.incomingEdges, this.outgoingEdges].forEach(function (edgeList) {
+        Object.keys(edgeList).forEach(function (key) {
+          var idx = edgeList[key].indexOf(node);
+          if (idx >= 0) {
+            edgeList[key].splice(idx, 1);
+          }
+        }, this);
+      });
+    }
+  },
+  /**
+   * Check if a node exists in the graph
+   */
+  hasNode: function (node) {
+    return this.nodes.hasOwnProperty(node);
+  },
+  /**
+   * Get the data associated with a node name
+   */
+  getNodeData: function (node) {
+    if (this.hasNode(node)) {
+      return this.nodes[node];
+    } else {
+      throw new Error("Node does not exist: " + node);
+    }
+  },
+  /**
+   * Set the associated data for a given node name. If the node does not exist, this method will throw an error
+   */
+  setNodeData: function (node, data) {
+    if (this.hasNode(node)) {
+      this.nodes[node] = data;
+    } else {
+      throw new Error("Node does not exist: " + node);
+    }
+  },
+  /**
+   * Add a dependency between two nodes. If either of the nodes does not exist,
+   * an Error will be thrown.
+   */
+  addDependency: function (from, to) {
+    if (!this.hasNode(from)) {
+      throw new Error("Node does not exist: " + from);
+    }
+    if (!this.hasNode(to)) {
+      throw new Error("Node does not exist: " + to);
+    }
+    if (this.outgoingEdges[from].indexOf(to) === -1) {
+      this.outgoingEdges[from].push(to);
+    }
+    if (this.incomingEdges[to].indexOf(from) === -1) {
+      this.incomingEdges[to].push(from);
+    }
+    return true;
+  },
+  /**
+   * Remove a dependency between two nodes.
+   */
+  removeDependency: function (from, to) {
+    var idx;
+    if (this.hasNode(from)) {
+      idx = this.outgoingEdges[from].indexOf(to);
+      if (idx >= 0) {
+        this.outgoingEdges[from].splice(idx, 1);
+      }
+    }
+
+    if (this.hasNode(to)) {
+      idx = this.incomingEdges[to].indexOf(from);
+      if (idx >= 0) {
+        this.incomingEdges[to].splice(idx, 1);
+      }
+    }
+  },
+  /**
+   * Return a clone of the dependency graph. If any custom data is attached
+   * to the nodes, it will only be shallow copied.
+   */
+  clone: function () {
+    var source = this;
+    var result = new DepGraph();
+    var keys = Object.keys(source.nodes);
+    keys.forEach(function (n) {
+      result.nodes[n] = source.nodes[n];
+      result.outgoingEdges[n] = source.outgoingEdges[n].slice(0);
+      result.incomingEdges[n] = source.incomingEdges[n].slice(0);
+    });
+    return result;
+  },
+  /**
+   * Get an array containing the direct dependencies of the specified node.
+   *
+   * Throws an Error if the specified node does not exist.
+   */
+  directDependenciesOf: function (node) {
+    if (this.hasNode(node)) {
+      return this.outgoingEdges[node].slice(0);
+    } else {
+      throw new Error("Node does not exist: " + node);
+    }
+  },
+  /**
+   * Get an array containing the nodes that directly depend on the specified node.
+   *
+   * Throws an Error if the specified node does not exist.
+   */
+  directDependantsOf: function (node) {
+    if (this.hasNode(node)) {
+      return this.incomingEdges[node].slice(0);
+    } else {
+      throw new Error("Node does not exist: " + node);
+    }
+  },
+  /**
+   * Get an array containing the nodes that the specified node depends on (transitively).
+   *
+   * Throws an Error if the graph has a cycle, or the specified node does not exist.
+   *
+   * If `leavesOnly` is true, only nodes that do not depend on any other nodes will be returned
+   * in the array.
+   */
+  dependenciesOf: function (node, leavesOnly) {
+    if (this.hasNode(node)) {
+      var result = [];
+      var DFS = createDFS(
+        this.outgoingEdges,
+        leavesOnly,
+        result,
+        this.circular
+      );
+      DFS(node);
+      var idx = result.indexOf(node);
+      if (idx >= 0) {
+        result.splice(idx, 1);
+      }
+      return result;
+    } else {
+      throw new Error("Node does not exist: " + node);
+    }
+  },
+  /**
+   * get an array containing the nodes that depend on the specified node (transitively).
+   *
+   * Throws an Error if the graph has a cycle, or the specified node does not exist.
+   *
+   * If `leavesOnly` is true, only nodes that do not have any dependants will be returned in the array.
+   */
+  dependantsOf: function (node, leavesOnly) {
+    if (this.hasNode(node)) {
+      var result = [];
+      var DFS = createDFS(
+        this.incomingEdges,
+        leavesOnly,
+        result,
+        this.circular
+      );
+      DFS(node);
+      var idx = result.indexOf(node);
+      if (idx >= 0) {
+        result.splice(idx, 1);
+      }
+      return result;
+    } else {
+      throw new Error("Node does not exist: " + node);
+    }
+  },
+  /**
+   * Construct the overall processing order for the dependency graph.
+   *
+   * Throws an Error if the graph has a cycle.
+   *
+   * If `leavesOnly` is true, only nodes that do not depend on any other nodes will be returned.
+   */
+  overallOrder: function (leavesOnly) {
+    var self = this;
+    var result = [];
+    var keys = Object.keys(this.nodes);
+    if (keys.length === 0) {
+      return result; // Empty graph
+    } else {
+      if (!this.circular) {
+        // Look for cycles - we run the DFS starting at all the nodes in case there
+        // are several disconnected subgraphs inside this dependency graph.
+        var CycleDFS = createDFS(this.outgoingEdges, false, [], this.circular);
+        keys.forEach(function (n) {
+          CycleDFS(n);
+        });
+      }
+
+      var DFS = createDFS(
+        this.outgoingEdges,
+        leavesOnly,
+        result,
+        this.circular
+      );
+      // Find all potential starting points (nodes with nothing depending on them) an
+      // run a DFS starting at these points to get the order
+      keys
+        .filter(function (node) {
+          return self.incomingEdges[node].length === 0;
+        })
+        .forEach(function (n) {
+          DFS(n);
+        });
+
+      // If we're allowing cycles - we need to run the DFS against any remaining
+      // nodes that did not end up in the initial result (as they are part of a
+      // subgraph that does not have a clear starting point)
+      if (this.circular) {
+        keys
+          .filter(function (node) {
+            return result.indexOf(node) === -1;
+          })
+          .forEach(function (n) {
+            DFS(n);
+          });
+      }
+
+      return result;
+    }
+  },
+  /**
+   * Get an array of nodes that have no dependants (i.e. nothing depends on them).
+   */
+  entryNodes: function () {
+    var self = this;
+    return Object.keys(this.nodes).filter(function (node) {
+      return self.incomingEdges[node].length === 0;
+    });
+  }
+};
+
+// Create some aliases
+DepGraph.prototype.directDependentsOf = DepGraph.prototype.directDependantsOf;
+DepGraph.prototype.dependentsOf = DepGraph.prototype.dependantsOf;
+
+/**
+ * Cycle error, including the path of the cycle.
+ */
+var DepGraphCycleError = (exports.DepGraphCycleError = function (cyclePath) {
+  var message = "Dependency Cycle Found: " + cyclePath.join(" -> ");
+  var instance = new Error(message);
+  instance.cyclePath = cyclePath;
+  Object.setPrototypeOf(instance, Object.getPrototypeOf(this));
+  if (Error.captureStackTrace) {
+    Error.captureStackTrace(instance, DepGraphCycleError);
+  }
+  return instance;
+});
+DepGraphCycleError.prototype = Object.create(Error.prototype, {
+  constructor: {
+    value: Error,
+    enumerable: false,
+    writable: true,
+    configurable: true
+  }
+});
+Object.setPrototypeOf(DepGraphCycleError, Error);