Travis: Add travis yaml

[1480c1]

Add windows, linux python2.7 and pypy2.7 Add coverage support

It is necessary to activate travis at https://travis-ci.com/ to start testing. The windows build are possibly blocked because of #61

There are still more tests that can be added if needed. It's possible to set it up so that the

coverage will be sent to https://coveralls.io if that is setup, it can be removed if its unnecessary