Add more service types to avoid salt-minon exception

If ceph-fuse is deployed, a socket named "ceph-client.admin.asok" would appear under
`/var/run/ceph`, and cause current code AttributeError. So this patch will
1) add "client" to the regular expression matching pattern
2) ignore AttributeError from method service_status(), to avoid potential errors in future
slight misunderstanding - when I say "service name" I mean like the ID of it, e.g. if someone has mon.myhostname then I'm talking about the "myhostname" part.  The mon/mds/osd/rgw/client part of it will never contain any punctuation.