- move loading indicator into search result container
- update list of communities even when no results is being returned
- clean up code

A simple list of communities and whether or not the current user is subscribed to them.

Issues:
- [ ] Context is not being returned so I can't see if the user is subscribed
- [ ] CSS and data munging + edge cases
- [ ] Subscribe buttons are not updating when state changes.

Fixes #3507

When a user clicks "Create Post" from a community page, the editor will have that community prefilled as the main category for that post.

Screenshots:

Issues:
- WIP