[pydotorg-www] Python 3 porting poll

["Martin v. Löwis"]

I just installed a poll on www.python.org that allows users to nominate
packages that they want to see ported to Python 3.

Feel free to adjust the wording or design of the poll itself, or the
results. If this causes problems, don't hesitate to disable it again.

Changes don't propagate automatically on commit, you have to manually
update /data/website-build/build/scripts/poll3k.py, or
/data/website-build/build/new-build/homepage.tmpl.

Regards,
Martin