Merge pull request #13 from ulikoehler/compatnote

Expand compatibility list to Python 3.x

move installation further down readme

Merge pull request #6 from ulikoehler/set_periods

Merge pull request #12 from aaren/travis-py3

travis: only test pep8 once

travis: test python 3

Merge pull request #11 from ulikoehler/imgoverwrite

Merge pull request #9 from ulikoehler/python3

Merge pull request #10 from ulikoehler/requirements

Rename example graphics so they don't get overwritten by unit tests

Added requirements.txt and documentation on how to install

Import print_function from __future__

Make print calls python3 compatible

Added fourier_periods basic test