BZ #1134139 - Track Real User behind SSH logins

If we roll this out I'm thinking there will be a period of time when authorized_keys entries will be missing the OPENSHIFT_LOGIN variable.  If we go with the special 'S' and 'A' values (or any special value) would probably be good to add a warning if OPENSHIFT_LOGIN was ever missing.  It could simply advise the admin to have owners of application $uuid to re-add their ssh keys.  I'm assuming that would be the simplist way for them to have the new OPENSHIFT_LOGIN set.