Do not compare edge properties when adding edge
Do not compare edge properties when adding edge

- Previously edge properties were compared when adding a new edge
  from statements. This was done to add the uuid to an edge that may
  be identical to another one instead of generating another edge.
  Because only i, source, target, polarity, were compared, it is possible
  to not treat statements that differ in a modification (e.g. - phospho
  site) as the same, and not generate another edge for the statement.
- This was not the intended behavior.
- Upon closer examination, each edge comes from a single statement at
  initialization. As such, it should have only one uuid. This is what should
  make it into the edge.
- Edge grouping will handle the comparison and grouping of edges between
  nodes.

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