ceph_manager: reset osd weights to 1 when waiting for clean

If we leave the weights adjusted, we can get PGs stuck in a remapped state
because we are probabilistically rejecting placement.  Avoid this by
setting on in osds to 1.0 before waiting for clean.

Signed-off-by: Sage Weil <sage@inktank.com>
Merge pull request #250 from ceph/wip-fix-thrasher

ceph_manager: reset osd weights to 1 when waiting for clean

Reviewed-by: Josh Durgin <josh.durgin@inktank.com>