Reduce the number of database queries done by the Submission.get_flags method in the demos app.

Do some PEP8 work while I’m here.
Fixed a few import errors.
Maintain the wiki JavaScript scripts, avoid another script load
Merge pull request #1860 from darkwing/wiki-scripts

Maintain the wiki JavaScript scripts, avoid another script load
Revert "Use Memcache and clean up caching setup."

This reverts commit 728e5bc83ca6fc023f90d6b9745e12f4601f85de.

Conflicts:
	settings.py
Merge pull request #1881 from groovecoder/revert-memcache-setup

Revert "Use Memcache and clean up caching setup."
Merge pull request #1875 from jezdez/taggit-homepage-queries

Reduce the number of database queries done by the Submission.get_flags method in the demos app.
Fix namespace collision with deleted documents manager.
Merge pull request #1883 from ubernostrum/document-deleted-manager

Fix namespace collision with deleted documents manager.