Add a couple of notes about deployment
Add a quick process for deploying without re-building
Remove duplicate item
Simplify 500.html, so that it doesn't extend any templates

This makes it a bit easier to see what things it relies on,
and minimise its dependencies.
Add a note about permissions and the input widget
Having the last modified time view is just noise
Move slice_results to a base class
Paginate results from the attachment widget
Short-circuit for superusers
You don't need permission to manage media to add media to things
Don't ask users to upload things they aren't allowed to
Fixing popup layout, post the move to BS3
Fixing bad imports, and flake8