Entirely rework cycle canceling algorithms (#180)

- Move the cycle canceling algorithms (CycleCanceling, CancelAndTighten)
into one class (CycleCanceling).
- Add a Method parameter to the run() function to be able to select
the used cycle canceling method.
- Use the new interface similarly to NetworkSimplex.
- Rework the implementations using an efficient internal structure
for handling the residual network.
This improvement made the codes much faster.
- Handle GEQ supply type (LEQ is not supported).
- Handle infinite upper bounds.
- Handle negative costs (for arcs of finite upper bound).
- Extend the documentation.

 /* The version string */

 #undef LEMON_VERSION

 /* Define to 1 if you have long long */

 #undef LEMON_HAVE_LONG_LONG

 /* Define to 1 if you have any LP solver. */

 #undef LEMON_HAVE_LP

 /* Define to 1 if you have any MIP solver. */

 #undef LEMON_HAVE_MIP

 /* Define to 1 if you have CPLEX. */

 #undef LEMON_HAVE_CPLEX

 /* Define to 1 if you have GLPK. */

 #undef LEMON_HAVE_GLPK

 /* Define to 1 if you have SOPLEX */

 #undef LEMON_HAVE_SOPLEX

 /* Define to 1 if you have CLP */

 #undef LEMON_HAVE_CLP

 /* Define to 1 if you have CBC */

 #undef LEMON_HAVE_CBC