Support for optimize

[domoritz]

If I have soft constraints, this library gives me multiple results and also does not return the penalty for the different optimizations.

I saw yield_stats but it's not passed through from clyngor.solve.

[Aluriak]

I just updated clyngor to 0.1.0, that now handle access to stats and optimizations.

solver = clyngor.solve(...)
solver.stats  # it's a dict

for answer, opt in solver.with_optimization:
    # opt is the optimization score

Note that the stats are copy pasted raw into a dict, without any consideration for the eventual doublons or hierarchy.

[Aluriak]

In case you update : the optimization score is now a list of integers, enable support of multiple optimization scores.