WIP because BE MR isn't merged yet pleroma!2160 (merged)

Fixes:

• input box width in reaction picker
• emoji reactions in the smaller fav/rt notifs removed

Changes:

• use updated "reacted" property in emoji reactions (not merged into develop yet in be)
• real time updating for your own statuses when they get reactions

Added:

• A hider for too many emoji reactions per status, can be toggled
• show list of reacted users on mouseover
• notifications when someone reacts to your status (disabled by default for less spam in notifs)
• option to disable emoji reactions on timeline, however they will remain on focused statuses. motivation: allowing people to keep their timelines more compact with less clutter when scrolling through