RF: clean up doc strings, add exception to try,except, PEP8
RF: Partition inherits from object to handle community property properly, add doc strings
PEP8 and cleaning docstrings
RF: Partition changed to WeightedPartition
RF: change community to communities to clarify code readability
RF: move modularity into WeightedPartition class
RF: move dnodecom and node_degree into WeightedPartition object
RF: create LouvainCommunityDetection class, move functions into new class
TEST: add test for Louvain class, communities_without_node
TEST: finish refactoring tests for new LouvainCommunityPartition class
RF+TEST: added more tests, cleaned up LouvainCommunityPartition class