swap_an_edgeC: Swap a single edge (method 2 in C++)
In jhrcook/wext: Weighted Exclusivity Test (WExT)

Swap an edge of a bipartite graph while maintaining the bipartite nature. This function is not perfectly named as it runs more than a single edge swap (whereas the R implemented functions only run a single swap).

1	swap_an_edgeC(n1, n2, N, max_try, quiet)

`n1, n2`	the graph built as a set of two vectors with the nodes for each edge
`N`	the number of edges to swap (one at a time)
`max_try`	number of times to try to find two edges to swap; no message is relayed for a single unsuccessful edge swap - instead a message at the end prints the number of successful edge swaps in total
`quiet`	boolean for if you want a message if not `N` edge swaps are performed