devilry_developer.testhelpers.corebuilder: Renamed GroupBuilder to AssignmentGroupBuilder.
devilry_developer.testhelpers.corebuilder: Cleanup.
devilry_developer.testhelpers.corebuilder: Added add_delivery_x_hours_before|after_deadline.
devilry_developer.testhelpers.corebuilder: Docs.
docs.devilry_developer.teshelpers.corebuilder: Cleanup.
devilry_developer.testhelpers.corebuilder: Always create DevilryUserProfile

when creating a user.
docs.mock: Very short Mock document.
docs.devilry_developer.teshelpers.corebuilder: Include imports in examples.