Merge PR #25272 into master

Merge PR #25272 into master

* refs/pull/25272/head:
	qa: add simple test-volumes.sh workunit and run it from fs/basic_functional
	vstart.sh: create default fs via 'fs volume create'
	mgr/volumes: fix oremote
	mon/MgrMonitor: enable volumes module by default
	mgr: create `volumes` module
	mgr: cleaner constructor for CommandResult
	mgr: block for latest osdmap after command execution
	mgr: add MgrModule.mon_command helper
	ceph_volume_client: enable using existing rados inst
	mon: give ceph-mgr access to 'fs' commands

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Fajerski <jfajerski@suse.com>