Remove rs_rollback_no_uuid files after MongoDB 3.6

After MongoDB 3.6 is released, all oplogs will be required to have a UUID entry, making the no_uuid rollback files unnecessary. rs_rollback_no_uuid.cpp/.h and rs_rollback_no_uuid_test.cpp should all be removed at this point. Additional code that allowed for the old rollback algorithms to work should also be deleted. The failpoint declarations

// Failpoint which causes rollback to hang before finishing.

MONGO_FP_DECLARE(rollbackHangBeforeFinish);

// Failpoint which causes rollback to hang and then fail after minValid is written.

MONGO_FP_DECLARE(rollbackHangThenFailAfterWritingMinValid);

should be moved out of roll_back_local_operations.cpp/.h and moved into rs_rollback.cpp after rs_rollback_no_uuid.cpp/.h are deleted. The Sconscript will need to be adjusted accordingly as well.