fixed group node generation. added comments. nodes within a group would point to a group's name not a group's id. added some comments to make it more clear what parts of code do.
fixed group node generation. added comments.
nodes within a group would point to a group's name not a group's id.
added some comments to make it more clear what parts of code do.

sorgerlab/indra,sorgerlab/belpy,jmuhlich/indra,johnbachman/belpy,pvtodorov/indra,pvtodorov/indra,johnbachman/belpy,pvtodorov/indra,johnbachman/indra,jmuhlich/indra,bgyori/indra,johnbachman/indra,sorgerlab/belpy,bgyori/indra,sorgerlab/indra,sorgerlab/indra,sorgerlab/belpy,jmuhlich/indra,johnbachman/indra,johnbachman/belpy,bgyori/indra,pvtodorov/indra