More py3.3 compat changes. Remove unused type classes, import unicode literals
travis py 3.3
Tests pass in python 3.3

Import py3.3 stuff from __future__
Various checks to change behaviour in py3
update lxml version
Use six todo py3.3 compat stuff
Output __str__ in the given encoding

Removes need to is PY3 checks
Merge pull request #6 from minimal/py33

Py33 compatibility 
requirements not needed for travis
Merge branch 'develop'