Rename mcv.{deploy,remote}

This more accurately describes what the module's stuff is doing.
Swap fabric->paramiko in setup.py

The remote facilities in MCV will be powered by Paramiko, not
Fabric.
Add .gitignore
Decompose dpkg functionality in apt module

By breaking apart the functions we can use some of the dpkg logic
so that it works either locally or remotely.  Once you've gotten
the dpkg output (either locally from subprocess, or remotely over
SSH), the same exact functions can parse it etc.

This will help us build the mcv.remote.apt module in a forthcoming
commit.
Add requirements.txt

This helps set up the development requirements for MCV conveniently.
Add mcv.remote.apt

This commit adds mcv.remote.apt, which allows us to install APT
packages remotely over SSH.  It composes the standard mcv.remote
functions with the mcv.apt functions to do APT work remotely.