[bug-fix] nElementsA was being decremented when calling to removeNeighbor for a non-neighbor in AbstractTwoSidedFactor.
Better testing of AbstractTwoSidedFactor
Merge pull request #10 from tonipenya/master

[bug-fix] nElementsA was being decremented when calling to removeNeighbor for a non-neighbor in AbstractTwoSidedFactor.