Rerun makemessages on wagtailembeds
Run makemessages on wagtailforms
More granular group view permissions checks
Implement group delete functionality
Rerun makemessages on wagtailredirects
Templates folder structure tidy
Rerun makemessages on wagtailusers
Rerun makemessages on wagtailimages
Rerun makemessages on wagtailsearch
Rerun makemessages on wagtailsnippets
Run makemessages on wagtailstyleguide
Merge pull request #464 from kaedroho/makemessages

Rerun makemessages
Elasticsearch: Cast __in lookup values to list

This makes sure lazily-evaluated lists (like querysets) are evaluated so they can be converted to JSON
Replaced lxml with html5lib
Fixed test which broke under html5lib

The test used HTML which wasn't valid HTML5. html5lib corrects these errors whereas lxml didn't so the result of the test is different.
Improve 'used by/usage count' implementation

- used_by() generates a database query instead of looping over a list of
  objects.
- usage_count() removed. Call count() on the queryset returned by
  used_by()
- Changed USAGE_COUNT to WAGTAIL_USAGE_COUNT_ENABLED. Added an inclusion
  tag for it.
Fix unit test failures
Merge branch 'master' into 146-display-calculated-usage
Typos in 0.4 release notes
Added contents