add missing south migration - remove auto_add_now from page_revision.created_at and nullify page owner on user deletion
add migration to tests app to fix typo in formfield help text. (Most. Pointless. Migration. Ever.)
merge parallel migrations in tests
Merge branch 'master' of github.com:torchbox/wagtail
Fix some more python3.2-incompatible unicode strings in migration 11
Add a test that checks for missing migrations

If there are any outstanding model changes that have no migrations, the
tests will fail. Migrations *must* be up-to-date before any code changes
are accepted, or before a new version is released. If they are not, it
causes havoc for all users.

The bulk of the test code is taken from the Django 1.7 `makemigrations`
command, and the South `schemamigration` command.
Fix wagtailimage migrations not using AUTH_USER_MODEL

This caused a false-positive when South checked for changes to models
and an AUTH_USER_MODEL was being used.
Forgive me, debugging via Travis CI!