Reorganise project

- Add __init__.py files so module discovery works
- Move tests to sub-folder
- Change test imports to be relative

TODO: py.test only passes when run from tests subfolder.
Package project for distribution
Ignore packaging info
Make tests work when run from outside tests dir

- Delete __init__.py from tests dir as per pytest instructions
- Get and include absolute paths for test xml files
Ignore binary distribution
Fix import error caused by package restructuring
Fix imports
Update usage instructions
Integrate pytest with setup.py
Configure TravisCI to use setup.py as test script
Merge pull request #17 from graphiclunarkid/package

Package the project