[SyncEvolution] add new SQlite backend

Hello, i add the SQLiteCalendarSourceRegister.cpp and the SQLiteCalendarSource.cpp under sqlite backend , i modify makefile.am under sqlite backend and i modify the makefile.am under src by adding SQLiteCalendarSource.cpp to BACKEND_REGISTRIES. i try to compile but syncevolution ignore the calendar register file, please explain to me what should i do exactly ? THX.