OBMFULL-5626 Devices should not be able to modify Event sensitivity

Conflicts:
	java/sync/integration-testing/opush/src/test/java/org/obm/opush/command/sync/SyncHandlerWithBackendTest.java
	java/sync/opush/obm-backend/src/test/java/org/obm/push/calendar/MSEventToObmEventConverterExceptionTest.java