Python 3 fixes, other fixes

Coded the hell out of it.

- added .gitignore exceptions
- updated packages versions (+some dependencies rewritten)
- changed Travis build to test on Python 3.4 (+ PySide)
- updated code to meet PEP requirements and Python 3 support
- small tests updates

Relied mostly on existing test suite and Travis builds
"local variable 'url' is assigned but never used" (And as I remember six.u caused problems in some places! Like this one: https://github.com/makinacorpus/spynner/issues/64
As I remeber that was because of six.u()