So user is redirected to the correct page after uploading data

When process_items is called without a request, redirect to data-view (don't try to double guess the tab)

Provide the tab instance to get_context_data, and use that to work out the URL to redirect forms to.

Also added test

Remove outer html from the view and edit page, this is now taken care of by the tabbed page rendering.

-- flow both actions and save 'row' on small screens to be on one line - currently save button falling below field. (have reduced dropdown width on smallest screen only where this was a problem)

Don't use Bootstrap tabs for our tabbed navigation, as those are meant for single page applications, not for links that reload the page.

use view_name instead of name when getting tab out of the registry

Also refactored some of the tests to pick out the args of interest
sent to render_string

Register the template tag. Also use the view name, not the tab name, when fetching the tab to render.

Fix url patterns. We could fix the single regexp, but apparently best practice is to have this on multiple lines.

I'm surprised that JSONField isn't defaulting to {}, as it says
in the documentation. Need to investigate this.