This introduces a new per-user preference called
"Auto-play animated GIFs", which is enabled by default. When a
user disables this setting, gifs in toots become click-to-play.

Previews of animated gifs were changed to display the video play
button so that users can distinguish them from regular images.

This setting also affects account avatars in the detailed account
view, which was changed to use the same hover-to-play mechanism
that is used for animated avatars in timelines.

Fixes #1652

for those errors

The status is not showing anymore after clicking on it

Fix issue with detailed status view not supporting unreblogging/unfavouriting

nested inside a common parent (<Account>), instead they all embed <HeaderContainer />

on scrollable areas

all statuses/accounts to assemble, but at least lists don't have to be
re-rendered all the time now. Also add "mention" dropdown option

Also fix reloading of timelines after merge-type events

Also upgrade react-redux to latest version. This is a performance update

Also, only update relative time every minute instead of 6 seconds. My bad