Bug related to labelling in max_flow() method fixed. Updating labelling was forgotten in an if branch. I inserted the label update lines. I also commented out a redundant branch for arc color update, this branch is never executed.
Bug related to labelling in max_flow() method fixed. Updating labelling was forgotten in an if branch. I inserted the label update lines. I also commented out a redundant branch for arc color update, this branch is never executed.

git-svn-id: 3b9420f7568da4e67ed4a5406dba8e5ca52b1cc2@1124 5eb3cf9a-c56f-4155-9a08-806ae8551a6d

coin-or/GiMPy,coin-or/GiMPy