'"Flattens" a snapshotted image with the parents\' data,
effectively detaching it from the parent.
:volume: Name of RBD object
:pool: Name of pool'

def flatten(self, volume, pool=None):

    LOG.debug('flattening    %(pool)s/%(vol)s', dict(pool=pool, vol=volume))
    with RBDVolumeProxy(self, str(volume), pool=pool) as vol:
        vol.flatten()
