Fix MySQL termination system test

Check that MySQL is started by pacemaker after
forced daemon termination using its PID file and
resource status command.
Also fix error in 'wait_mysql_galera_is_up' method:
it raises an exception "'list' object has no attribute
'strip'" if execution of remote comand isn't sucessfull

Change-Id: I7b3d2450c6a5b6c5c19d0a93d80b2e107e452825
Closes-bug: #1339064
Merge "Fix MySQL termination system test"