Replaced super() by super(type, obj) to add support to Python 2.
Added support for CI (Travis) for Python 2.7 and 3.4.
Fixed #17 -- Added support to Python 2.7.

Also added supported Python versions to README. 2 previous commits
are part of this fix.
Improved setup.py.

- Fixed issue #12;
- Fixed name;
- Added classifiers.