Documentation support for copy_relations()
Added checks for page/title extensions and copy_relations to management commands
Move handling-relations to its own section for reference ability.
Implement copy_relations check for Page/Title extensions
Update extension app to include a M2M
Add tests for cms check and M2M field on pageextension
Update docs to match texted configuration
Use settings.AUTH_USER_MODEL
OK, use User for Django 1.4, use settings.USER_AUTH_MODEL for 1.5+
Remove testing against BaseExtension, not really possible anyway.
Remove test comparing a field to a model (Doh!)
Merge pull request #3002 from mkoistinen/page_extensions_support

Page extensions support adding docs, management command checks, and tests.