Merge pull request #256 from chocoteam/pr_iss253

issue#253: proposal
Merge branch 'develop' of https://github.com/chocoteam/Choco3 into develop
#253: fix bug
warning PropDiffN

remove warning from PropDiffN
warning

Remove warning from AbstractLengauerTarjanDominatorsFinder.java
warning

remove warning from StrongConnectivityFinder
warning

remove warning from LCAGraphManager
Merge branch 'feat-war' into feature_MCR

Conflicts:
	choco-solver/src/main/java/solver/constraints/set/PropIntEnumMemberSet.java
Fix #258