LP1378355 - Pass the value of --defaults-group-suffix to xtrabackup during SST
LP1378355 - Address review feedback, do not pass --defaults-group-suffix for mysqldump SST
LP1378355 - Reduce memory consumption slightly.
Merge pull request #30 from codership/lp1378355

LP1378355 - Pass the value of --defaults-group-suffix to xtrabackup during SST