New: Add "coverage" and "python-coveralls" to requirements.txt

I'm working on automated automated-test coverage reports with coveralls.io.
New: Coveralls.io Support in .travis.yml

Let's hope it works... !
Fixed: Update README.txt (also add coveralls.io to Same)
Fixed: Fix Travis's "script" Command
Fixed: Consistent Citation Year in README
New: Add .coveragerc File

Should have been in here a few commits ago. Oops!
Fix: Revise run_tests.py to Return non-0 Status on Test Failure

Previously, the script would return 0 unless there was an error with the file
itself. This was fine for humans reading test results, but it doesn't work with
Travis-CI, which needs a non-zero status to signify failure, so failing builds
where showing up as "passing" on Travis.

This also means the script stops on the first failure.