Bug #2271: remove '-O rbd' from qemu-img
(cherry picked from commit 3c8dbd669a906623359d35337bacb5d1261b54c4)
Bug #2271: rados command doesn't need sudo
(cherry picked from commit 72dc5e70a47cec6a0e14a37263fee160c4b2aca1)

Conflicts:
	src/datastore_mad/remotes/ceph/monitor