RF: remove unused Guimera modularity code
NF: method in GraphPArtition to check that index is a dict containing sets
NF: clear error raised if index does not contain all possible nodes
NF: added tests for new type checking methods of GraphPartition, and check that index is a dict
BF: fix modularity test passing index as improper type (list), and removed some cruft
RF: clean up 1/0 a bit, preparing for _check_integrity
Merge pull request #4 from cindeem/edits

GraphPartition value checking and cleaning
Add documentation to cost_size and cleanup style.
Start writing documentation for cost2thresh.
Cleanup and add documentation to threshold_arr and thresholded_arr.
Fix error I introduced to cost_size docstring.
Clean up and add documentation to cost2thresh.
Replace cost_size with new function make_cost_array.
Update old print statements to use print function.
Write apply_cost and its test.
Clean up and add documentation to nodal_pathlengths.
Start to clean up nodal_summaryOut.
Correct distance calculation for disconnected nodes.
Merge tests for nodal metrics into a TestCase.
Write inter_node_distances w/ test, update nodal metric functions.