* Add announcements
Fix#11006
* Add reactions to announcements
* Add admin UI for announcements
* Add unit tests
* Fix issues
- Add `with_dismissed` param to announcements API
- Fix end date not being formatted when time range is given
- Fix announcement delete causing reactions to send streaming updates
- Fix announcements container growing too wide and mascot too small
- Fix `all_day` being settable when no time range is given
- Change text "Update" to "Announcement"
* Fix scheduler unpublishing announcements before they are due
* Fix filter params not being passed to announcements filter
* Add backend support for bookmarks
Bookmarks behave like favourites, except they aren't shared with other
users and do not have an associated counter.
* Add spec for bookmark endpoints
* Add front-end support for bookmarks
* Introduce OAuth scopes for bookmarks
* Add bookmarks to archive takeout
* Fix migration
* Coding style fixes
* Fix rebase issue
* Update bookmarked_statuses to latest UI changes
* Update bookmark actions to properly reflect status changes in state
* Add bookmarks item to single-column layout
* Make active bookmarks red
