Introduced two new wsrep_mode options
* REPLICATE_MYISAM
* REPLICATE_ARIA
Depracated wsrep_replicate_myisam parameter and we use
wsrep_mode = REPLICATE_MYISAM instead.
This required small refactoring of wsrep_check_mode_after_open_table
so that both MyISAM and Aria are handled on required DML cases.
Similarly, added Aria to wsrep_should_replicate_ddl to handle DDL
for Aria tables using TOI. Added test cases and improved MyISAM testing.
Changed use of wsrep_replicate_myisam to wsrep_mode = REPLICATE_MYISAM
During total-order replication, Query_log_event's checksum_alg
should be explicitly set to the current binlog_checksum as it
is not set for DML queries.
Note: wsrep_replicate_myisam enables replication of DMLs on
MyISAM tables using TOI.
