The Pacific release of Ceph disabled 1x replication by default, and
some of the gate scripts are not updated to allow this explicitly.
Some gate jobs fail in some configurations as a result, so this
change adds 'mon_allow_pool_size_one = true' to those Ceph gate
scripts that don't already have it, along with
--yes-i-really-mean-it added to commands that set pool size.
Change-Id: I5fb08d3bb714f1b67294bb01e17e8a5c1ddbb73a
f80049faa1