Flocker deploy 121

I would like this to be looked over by someone, for guidance on what needs to be done, and confirmation I'm on the right track.

And, now, the comment on #121 that some of this might not be necessary for now.

There are a couple of inline "TODO"s I'm not sure about.

Fixes #121 
Always interpolate a tuple.

Relatedly but separately, we might want to think about standardizing on "{}".format(...) I guess.  This doesn't need to be addressed here though.