install rules for init-rbdmap

Signed-off-by: Laurent Barbe <laurent@ksperis.com>
Move rbdmap file to /etc/ceph

Signed-off-by: Laurent Barbe <laurent@ksperis.com>
Merge pull request #390 from ksperis/rbdmap.init-2

init-rbdmap install

Reviewed-by: Sage Weil <sage@inktank.com>