Skeletal test harness

To run, `./test.py`

The test harness sets an environment variable before importing config.py, which
tells config to use a "test environment" (store dir, key dir, and journalist
key) instead of the production environment.

I created a journalist keypair and included it in the repo for testing.
Generating a GPG keypair can be very time-consuming, and we want to be able to
run tests as fast as possible. The keypair is clearly marked so it is not used
by anyone for anything besides testing this application.
Merge pull request #65 from garrettr/tests

Skeletal test harness
Remove installRails function and doc references
Don't version control config.py

We should only keep the config template in git. Keeping config.py (even as
a symlink) creates all kinds of problems:

1. modifying it for your deploy shows up as local changes
2. easy to accidentally `git commit -a` and push sensitive data
3. doesn't correspond to the instructions in HACKING.md
Add JOURNALIST_KEY instructions for developers

Some rearranging for a clearer set of instructions, minor style fixes.
Merge pull request #66 from GabeIsman/removerails

Remove installRails function and doc references
Merge remote-tracking branch 'upstream/master'
changed tabs to spaces in hacking.md, and added python-dev dep