Move network_simplex out of mincost.py
Fix source encoding for python3 compatibility
Add capacity scaling minimum cost flow algorithm
Allow BinaryHeap to handle incomparable keys
Add documentation for capacity_scaling
Fix comment in capacity_scaling
Remove shortest path example from capacity_scaling doc
Fix bug that stoer_wagner ignores weight parameter
Merge pull request #1112 from ysitu/stoer_wagner

Fix bug that stoer_wagner ignores weight parameter
Merge pull request #1107 from ysitu/capacity_scaling

Add capacity scaling mincost flow algorithm