Removed remaining call to claroline.database.writer service
Removed remaining calls to claroline.database.generic_repository service
Removed Database folder and refactored accordingly
Unskipped tests in ResourceTypeRepositoryTest and ToolRepositoryTest
Updated phpunit.xml + set var  to private in RepositoryTestCase
Merge pull request #120 from kitan1982/refactoring-writer-and-genereic-repository

Refactoring writer and generic repository