prevent osd warnings from failing CephFS tests

Signed-off-by: Greg Farnum <greg@inktank.com>
rbd: add qemu-iotests

Put these in the singleton collection since they have to be run as
client.admin, which is possible when the client and monitor are on the
same host.

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
turn on debugging for MDS and Client in FS runs

Signed-off-by: Greg Farnum <greg@inktank.com>
set 'filestore flush min = 0' for all ffsb jobs

Until we fix #4579
Merge branch 'next'