Merge pull request #1 from antonycohen/master

GROUP BY
[GROUP BY] Fix count selector
[MEMCACHE] Add version to invalidate keys
[SPHINX] Fix offset and limit type. Cast to int
[SELECTOR] Can use alias in criterias (like m.id)
[TESTS] Fix it \!
[SELECTOR] Can join multiple times the same table (#2).
[SPHINX] Fix connection error : throw Exception
[AUTOLOAD] Fix autoload prefix
[TESTS] Reorganize tests
[TRAVIS] Add travis configuration file
[TRAVIS] Add travis indicator
[VALIDATOR] Add Symfony2 Unique Validator
[VALIDATOR] Fix
[FORM] Add form entity type
Update LICENSE
[FORM] Fix get Values For Choices
[ENTITY FORM LIST] Compare Ids only if choice and value are set
[DOC] First draft
[SELECTOR] Some fixes