Add a way to remove a node and all dependant nodes from a DepGraph instance

[waddlesplash]

As in title. Say I have a node that's in the "middle" -- it has some dependents and some dependencies. I want to remove this node and all of its dependent nodes (and all of their dependent nodes) from the dependency graph.

I have a semi-hacky solution that does this, but it'd be nice if dependency-graph had a function to do it.

[jriecken]

The dependenciesOf and dependantsOf function both return the full set of nodes that depend on, or are depended on by the given node (i.e it's not just the direct dependencies/dependants)

Seems like you could do this pretty easily with the existing API - E.g.

// Make a graph that looks like
//   /-- 2 -- 4 --\
//  1              6
//   \-- 3 -- 5 --/

var g = new DepGraph();
g.addNode('1');
g.addNode('2');
g.addNode('3');
g.addNode('4');
g.addNode('5');
g.addNode('6');
g.addDependency('1', '2');
g.addDependency('1', '3');
g.addDependency('2', '4');
g.addDependency('3', '5');
g.addDependency('4', '6');
g.addDependency('5', '6');

// Remove Node 5 and everything that depends on it

g.dependantsOf('5').forEach(function (n) { g.removeNode(n); });
g.removeNode('5');

// The graph is now
//       2 -- 4 --\
//                 6
//   

[waddlesplash]

That's an OK workaround, I suppose.