Add Document authorship info

NOTE: Document objects need to be deleted before the DB migration is run.
Add support for importing just a single document
Fix a typo in render_member_activity (showing initiatives failed)
Use cache-based session engine for better performance
Add info on how to configure Varnish
Enable caching on API resources
Import fix for some documents
Add option '--from-year' to allow starting the import from a given year
Remove django_assets
Convert tagcloud into 2013 and use non-minified jQuery expander
Add support for rendering more activity types
Working MP keyword activity tag cloud \o/
Fix leftover import
Add support for importing Twitter feeds
Allow Pvm field to go missing when importing question processing info
Store the list HTML docs in separate directories when importing
Add decorator for timing functions
Nuke a lot of unused directories
Fix FB picture update bug
REST-based member activity feed rendering