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 
And add a `longdesc` attribute with some description of those two positional arguments. See http://twistedmatrix.com/trac/browser/tags/releases/twisted-14.0.0/twisted/python/usage.py#L527