Add logic to clean binlog directory in PXB SST

[Raghavendra D Prabhu]

When it is defined separately in log-bin to a non $DATA path.

[Ryan Gordon (ryan-5)]

I was looking at the fix here http://bazaar.launchpad.net/~percona-core/percona-xtradb-cluster/5.6/revision/697 and I'm concerned there could be a regression here. Not knowing any better our bin log directory shares with the /var/log/mysql directory so it looks like that command, during an SST would delete all of the logs and whatever else was in that directory as well. I'm thinking the delete should be more specific, maybe only delete files beginning with "bin." as the prefix

[Raghavendra D Prabhu (raghavendra-prabhu)]

@Ryan,

When you are providing a separate directory for binlog, it is
always better to make it dedicated (and also since binlog is
unlike other 'logs' that are produced). In any case, I will make it that way.

[Raghavendra D Prabhu (raghavendra-prabhu)]

Added the fix for cleaning with prefix.

[Ryan Gordon (ryan-5)]

Thanks Raghu! That's good advice as well, we will definitely look into changing the bin log directory

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PXC-1597