Many patches, untested: TODO - extract out and rebase onto master
branch at later convenience.

Also introduces 1 test failure.
Fixing issue with django 1.3
Changing MEDIA_URL to STATIC_URL
Style fix for large month cal display when space available < 800px
Using AutoSlugField on Calendar/Event
Adding common base template for calendars
Extracting out common media into base template
Correcting templates now that occ.name doesn't auto-proxy to occ.event.name
Removing published attr from AttendanceQuerySet/Manager
Quick CSS tweak
Beter markup for month display of occurrences
Changing current navigation in favour of gcal-esque 'current' button
Minor template fixes
More descriptive and unique HTML titles for calendar/agenda pages
Improving display of tri-month calendar...

when displayed months have a differing number of rows.
Adding tests for persist_query_string tag, sorting

.. Which is to say, the qsl manipulation tags/filters now automatically
sort the querystring. This is both easier to test for, AND means that
search engines won't penalise webmasters for having identical content on
differing urls (/?a=foo&b=bar vs. /?b=bar&a=foo).
Adding tests for columns template filter
Cosmetic change
Adding padding/filler behaviour to the columns filter
Changing default behaviour of columns template filter

This change was made in particular to address the fact that the day
calendar columns displayed unattractively when the number of rows
created via TIMESLOT_START_TIME and TIMESLOT_END_TIME_DURATION was an
odd number.