Regeneralize deployment

Fully move all driver- and switch- dependent code from deployment tests into drivers.  (The deployment tests still depend on the concept of a vlan, but that's it.  Moving that code would be a little weirder, because the third test explicitly depends on that concept of vlan allocation, I believe.)
A comment summarizing what the regex does (e.g. "matches e.g. 'gi1/0/4'") would be a good idea.