mgmt/glusterd: Regenerate client volfiles during upgrade

Change-Id: I1442bc1d115a9c6ecf139a0ca9da74d07e0fe928
BUG: 1003855
Signed-off-by: shishir gowda <sgowda@redhat.com>
Reviewed-on: http://review.gluster.org/5764
Reviewed-by: Amar Tumballi <amarts@redhat.com>
Reviewed-by: Kaushal M <kaushal@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>