glusterd: Added op-version checks to geo-rep commands.

Added op-version checks to all geo-rep commands. Min
op-version should be 2.

Change-Id: I942d897404e11e4d53123409731ba5cd252668fe
BUG: 847839
Signed-off-by: Avra Sengupta <asengupt@redhat.com>
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-on: http://review.gluster.org/5732
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Amar Tumballi <amarts@redhat.com>
Reviewed-by: Anand Avati <avati@redhat.com>