Earlier, brick creation is carried out based on the difference of used
and unused bricks. This is a bottleneck for implementing brick
multiplexing testcases. Moreover we can't create more than 10 volumes.
With this library, implementing a way to create bricks on top of the
existing servers in a cyclic way to have equal number of bricks on each
brick partition on each server
Added paramter in setup_volume function, if multi_vol flag is set it
will fetch bricks using cyclic manner using (form_bricks_for_multi_vol)
otherwise it will fetch using old mechanism.
Added bulk_volume_creation function, to create multiple volumes the
user has specified.
Signed-off-by: Bala Konda Reddy M <email@example.com>