Explore Python 3 upgrade

From @philipn on August 4, 2013 20:38

This is a meta-issue tracking eventual, possible Python 3 support.

Packages we use and their status

Django -- Yes, as of Django 1.5. See #432.
html5lib -- Yes
sorl-thumbnail -- Kind of. https://github.com/sorl/sorl-thumbnail/pull/156 Patch here. Cold move to a different thumbnail library
python-dateutil -- Yes
pysolr -- Yes
haystack -- Yes
randomfilenamestorage -- Unclear. Probably no. Could port -- not a lot of code.
django-guardian -- Yes
South -- Yes
python-flot-utils -- Unclear.
django-staticfiles -- Probably.
django-registration -- Not yet. Can use https://pypi.python.org/pypi/django-reg or https://pypi.python.org/pypi/django-allauth
django-olwidget -- Unclear.
django-honeypot -- Unclear. Could fix as code is short.
django-tastypie -- Yes
django-qsstats-magic -- No.
django-picklefield -- Yes
constance -- Yes

So, need fixing: sorl-thumbnail, randomfilenamestorage, python-flot-utils, olwidget, honeypot, qsstats-magic.

Copied from original issue: localwiki/localwiki#588