An experimental LPSolverWrapper class which uses glpk. For a short
demo, max flow problems are solved with it. This demo does not
demonstrates, but the main aims of this class are row and column
generation capabilities, i.e. to be a core for easily
implementable branch-and-cut a column generetion algorithms.

 p mat 5 5

 a 1 3

 a 2 3

 a 3 5

 a 4 3

 a 5 4