First try: getting dependencies into setup.py

Fixed production dependencies are now in setup.py
`PROJECTROOT/requirements.txt` recursively includes
`requirements/production.txt`.

`requirements/production.txt` specifies `file:..#egg=budgetApp`, so
(in theory) setup.py's requirements would be used.

`requirements/development.txt` specifies budgetApp as editable and adds
some dev requirements.
Simpler installation step for travis