add setup.py script
add tox.ini

this allows to test the package with different python versions easily.

visit https://testrun.org/tox/latest/ for more information.
add travis ci configuration
Merge pull request #29 from brainbot-com/travisci

add setup script, tox config and travis ci config
remove python2.6 for travis
refine gitignore
close #27: ncomprehensible message when running behave tests