Create tests for top level r2s scripts (and refactor as needed)

[erelson]

The r2s_step1.py and r2s_step2.py scripts in particular need tests.

Some of the other scripts at the top level (r2s_setup.py and r2s_step2setup.py) also need tests.

I was looking at r2s_step2setup.py with this in mind, and ended up refactoring it into a handful of methods so that it's more testable. The same would probably be appropriate for the other scripts.

• r2s_setup.py
• r2s_step1.py
• r2s_step2.py
• r2s_step2setup.py

[erelson]

@elliottbiondo I've assigned this to you, tentatively; I've done step 2 and step 2 setup, which you can use as a guide for step 1. I also refactored both of those scripts to make them actually testable. Probably a good idea for r2s_step1.py as well.