* Fix#117 - Add ability to specify alternative text for media attachments
- POST /api/v1/media accepts `description` straight away
- PUT /api/v1/media/:id to update `description` (only for unattached ones)
- Serialized as `name` of Document object in ActivityPub
- Uploads form adjusted for better performance and description input
* Add tests
* Change undo button blend mode to difference
* Redesign video player
* Use new video player on static public pages too
* Use media gallery component on static public pages too
* Pause video when hiding it
* Full-screen sizing on WebKit
* Add aria labels to video player buttons
* Display link card on public status page
* Fix fullscreen from modal sizing issue
* Remove contain: strict property to fix fullscreen from columns
