Ensure strongly polynomial running time for CycleCanceling (#436)
The number of iterations performed by Howard's algorithm is limited.
If the limit is reached, a strongly polynomial implementation,
HartmannOrlinMmc is executed to find a minimum mean cycle.
This iteration limit is typically not reached, thus the combined
method is practically equivalent to Howard's algorithm, while it
also ensures the strongly polynomial time bound.
1 SET(LEMON_VERSION "@LEMON_VERSION@" CACHE STRING "LEMON version string.")