Support weights in edge partitioning

[DanielSeemaier]

Currently, the edge partitioning code ignores vertex and edge weights. This PR adds rudimentary support, but: for weighted input graphs, it might be harder to find "good" values for the "infinity" edge weight of dominant edges, i.e., one that is respected by the vertex partitioner and does not cause overflows. Contracting the dominant edges as in @adilchhabra 's code would be a much better option; maybe we should integrate his code instead? Would that be a lot of work or just plug'n'play? What do you think Adil?