Initial commit of unworking python betweenness impl
Adding non-working python code to begin translation.
Adding a Map implementation based on the one in Google Closure, but with
support for generic objects.
Updated betweenness and graph to start to use Map objects.
Initial commit supporting Object node keys.

This implementation uses a modified version of the Google Closure
library's goog.struct.Map

Not everything is working, but it's at least passing some of the basic
tests.
Merge https://github.com/jamiefolson/JSNetworkX

Much is still broken from the merge and from earlier changes

Conflicts:
	build.xml
	jsnetworkx.js
	jsnx/algorithms/cluster.js
	jsnx/classes/digraph.js
	jsnx/classes/graph.js
	jsnx/classes/multidigraph.js
	jsnx/classes/multigraph.js
	jsnx/convert.js
	jsnx/helper.js