first step to issue #110: simplify classes
last step to issue #110: refactor limits
add EXIT_ON_CLOSE option to JFrame
Merge branch 'feature-limit' into develop
Fix initial propagation of PropRegular
Merge branch 'feature-reg' into develop
udpate sql
Merge branch 'feature-sql' into develop
Merge branch 'develop' into feature-solution
merge

Conflicts:
	choco-solver/src/main/java/solver/search/loop/AbstractSearchLoop.java