Bug 1019672 Add steps: pip, setup.py and running unit tests.

@bitgeeky r? If everything looks ok to you, we can run it by Bob.
The packages here are specifically aimed for developer version as mentioned here [0]
We can mention it here if we want to add this.
[0] https://github.com/mozilla/oneanddone/blob/master/requirements/dev.txt#L1