add note that ceph.conf.template should no longer be modified
add note that ceph.conf.template should no longer be modified

Signed-off-by: Patrick Donnelly <d35c2028e065409a3eff47e1b4cba347a9379b4b@redhat.com>

SUSE/teuthology,SUSE/teuthology,dmick/teuthology,ceph/teuthology,dmick/teuthology,dmick/teuthology,ceph/teuthology,ktdreyer/teuthology,SUSE/teuthology,ktdreyer/teuthology