Better comments part #1

storage/rocksdb/mysql-test/rocksdb_rpl/t/disabled.def

+##
+##  Tests that require FB/MySQL specific features for which there are
+##  no plans to port them to MariaDB
+##
+rpl_no_unique_check_on_lag :  unique_check_lag_threshold is not available in MariaDB
+rpl_no_unique_check_on_lag_mts : unique_check_lag_threshold is not available in MariaDB
 
-# rpl_rocksdb_2pc_crash_recover 
+
+##
+## Tests that are disabled for other reasons 
+##
 
 consistent_snapshot_mixed_engines : Didn't try with MariaDB, yet
 multiclient_2pc : Didn't try with MariaDB, yet
@@ -8,8 +17,6 @@ rpl_ddl_high_priority : Didn't try with MariaDB, yet
 rpl_gtid_crash_safe : Didn't try with MariaDB, yet
 rpl_gtid_crash_safe_wal_corrupt : Didn't try with MariaDB, yet
 rpl_gtid_rocksdb_sys_header : Didn't try with MariaDB, yet
-rpl_no_unique_check_on_lag : Didn't try with MariaDB, yet
-rpl_no_unique_check_on_lag_mts : Didn't try with MariaDB, yet
 rpl_rocksdb_snapshot : Didn't try with MariaDB, yet
 rpl_rocksdb_snapshot_without_gtid : Didn't try with MariaDB, yet
 rpl_rocksdb_stress_crash : Didn't try with MariaDB, yet