Improvements in MinCostFlow and MinCostMaxFlow.

Main changes:
- MinCostMaxFlow also provides dual solution.
- Change the name of private members to start with "_".
- Change the name of function parameters not to start with "_".
- Remove unnecessary documentation for private members.
- Doc improvements.

 #!/bin/bash

 for((i=1;i<50;i++))

 do

     echo -n $i ''

     edge_lookup 100 $i

 done