Minor syntax updates to contributor stuff
fix bug 1000572 - Sync preview styles with documents
Update MathML fallback message
fix bug 1003033 - Add 'all revisions' button to profile
fix bug 906883 with browserid_form and csrf_exempt

This makes browserid_change_email work the same as browserid_verify,
since _verify_browserid on the assertion is an effective CSRF protection
fix bug 877679 - Final touches to launch 0.1 of search navigator
Merge pull request #2342 from darkwing/mathml-notice

Update MathML fallback message
Merge pull request #2343 from darkwing/user-edits-1003033

fix bug 1003033 - Add 'all revisions' button to profile
Merge pull request #2326 from darkwing/preview-1000572

fix bug 1000572 - Sync preview styles with documents
Moving home.css up by other CSS so it can be downloaded in parallel.
Make sure we use ES 0.20.5 and not the latest version (1.1.0).
Merge pull request #2346 from groovecoder/change-email-bug-906883

fix bug 906883 with browserid_form and csrf_exempt
Stop using python2.6-dev.
Merge pull request #2353 from jezdez/downgrade-elasticsearch

Make sure we use ES 0.20.5 and not the latest version (1.1.0).
Merge pull request #2348 from darkwing/877679-killer

fix bug 877679 - Final touches to launch 0.1 of search navigator
Merge pull request #2310 from darkwing/minor-contrib-updates

Minor syntax updates to contributor stuff
Merge pull request #2350 from darkwing/homepage-styles-order

Moving home.css up by other CSS so it can be downloaded in parallel.
Fix bug 972533: Enhancements to admin handling of deleted pages.

This adds a new manager to Document, which does not perform any
filtering based on deleted status, and uses that manager for the
admin; this ensures the admin always shows all Documents currently in
the database.

Building on that, the admin filters now include one to show only
deleted Documents.

The admin actions for Document are also updated:

* A new "purge" action is added, to bulk-purge deleted Documents.

* A new "undelete" action is added, to bulk-undelete deleted
  Documents.

* The built-in Django "delete" action is removed, since we want people
  using the standard deletion UI (and because the admin delete action
  bypasses the model delete() method, which is not what we want for
  deleting Documents).