Switched remote origin for smartd back to the upstream we were using and updated to head

The patch I needed has now been accepted in the upstream repo and so I've gone back to tracking that
Updated head ref of monkeysphere module for new version
dtg::minimal: turned on UsePAM option when configuring sshd

By turning this on we invoke the pam_motd module when you log in so you
can see the MOTD (and it gets regenerated). I'm using this on nas01 to
show the disk status at the moment.  The configuration leaves
PasswordAuthentication and ChallengeResponseAuthentication turned off so
I don't think we're opening up any new methods by doing this.