Add unit tests
Merge pull request #3 from alessione78/feature/openid-connect

Add unit tests
Added unitTest for entityFactory
Merge remote-tracking branch 'origin/feature/openid-connect' into feature/openid-connect
Merge branch 'feature/openid-connect' of https://github.com/thul/oauth2-server into feature/openid-connect
Refactored entityFactory
Merge branch 'feature/openid-connect' of https://github.com/thul/oauth2-server into feature/openid-connect
Added FactoryInterface
Merge branch 'feature/openid-connect' of https://github.com/thul/oauth2-server into feature/openid-connect
Use entity factory in ClientCredentialsGrant