there's been a lot of churn around this code, so i figure it was worth
trying to clean it up.
- the methods were doing a lot, so make them into template methods with
one helper per step
- spread out /etc/hosts regexp into a couple of helper variables for
clarity
- remove handling for broken hostname implementations (like basing all
of the checks on name.split('.')[0]), since it seems reasonable to
remove code dedicated only to handling broken boxes
- DRY up the shared code between debian/ubuntu implementations, which
clarifies the differences as well
- add unit tests around the behavior; this will help us in the future
to separate flaws in our understanding from flaws in implementation
- includes a new DummyCommunicator in tests which should be useful in
supporting additional unit testing of this kind
- manually tested this on squeeze, wheezy, precise, quantal, raring,
and saucy successfully.
handles the issue in #2333