* Check fragment removal error code in prepare phase. It is possible
that the transaction gets BF aborted during fragment removal.
* Mark fragment certified in certify_fragment() even if the provider
returns cert failed error. With current wsrep-API error codes
it may not be possible to distinquish certification failure
and BF abort during fragment replication. This may also be a
provider bug. As a result rollback fragment may sometimes be
replicated when it would not be necessary.
The interface method can be used to notify the DBMS implementation
about state changes in well defined order. The call will be done
under server_state mutex protection.
* Added bootstrap service call to do DBMS side bootstrap operations
during the cluster bootstrap.
* Added last_committed_gtid() to provider interface
* Implemented wait_for_gtid() provider call
* Pass initial position to the server state