ceph: wait_for_osds_up

Signed-off-by: Sage Weil <sage@inktank.com>
(cherry picked from commit 13aca3b7ade24451584cd566412f087d47e58f44)

Conflicts:

	teuthology/task/ceph.py
ceph: wait-for-osds-up option for restart

Signed-off-by: Sage Weil <sage@inktank.com>
(cherry picked from commit 75136a83227a7672e72a0ba20d278ec813d59416)