django 1.5 compatibility

The {url} template tag now needs quotes around the template name.
Context objects can't be dumped to JSON, so I need to do things properly in the search views.
The direct_to_template view function has gone, replaced with the TemplateView class
Mail handlers need a default set of filters.

Not sure if pagination of search results works, because I don't have enough questions on my test server. Should do!
default page for search requests
image uploads!

Image uploads work! Lots of jiggery-pokery to get them to work.
No interface in TinyMCE at the moment; just copy the URLs from the resources tab.
exams collect resources from their questions
image button picks the uploaded resources
convert some more URLs to django 1.5 syntax
fix another url; "none found" message; show resources on non-editable view
use django.conf.urls instead of "".default
delete resources; image attributes; image insert triggers update
trigger TinyMCE change after embedding a video
Upgrade to Django 1.5

Reorganise file layout.
Update settings
Merge branch 'master' into images
Merge branch 'images' of github.com:numbas/editor into images
Update ROOT_URLCONF
Remove extraneous print statements