[HBase] Catch AlreadyExists error in Connection upgrade

Now in upstream, if HBase table exists when we upgrade
backend AlreadyExists exception is raised. Also
exception raising interrupts creating of other tables.
It is an incorrect behavior because we should create
all tables and migrate them if need or use existing
tables.

Change-Id: I8e8a8ae633351de8393b5103910510dd635245be
Closes: bug #1370508
Merge "[HBase] Catch AlreadyExists error in Connection upgrade"