Port relevant parts of 9d4541c612 to glitch-soc

WARNING: This may break some custom skins!

  `.drawer > .contents` has been moved to
  `.drawer > .drawer__pager > .drawer__iner`, and the waves have been moved
  from `.drawer > .contents` to `.drawer__inner__mastodon`!

Port 66dbb59aa1 to glitch-soc

Port 0893b16695 to glitch-soc

Port c9cbb8de70 to glitch-soc

Port 7901f9f63e to glitch-soc

Port Mastodon's hashtag stats thing to glitch-soc.
This doesn't change how hashtags are ordered, and doesn't add a trending
hashtags section, but it does change how hashtag searches are rendered,
displaying a trend line alongside each hashtag.

This makes the clickable element an interactive element, but doesn't add
alt text and makes it not-obvious that you can click the elefriend.  On
one hand, this goes against good practice; on the other hand, it's not
*supposed* to be obvious that you can click the elefriend.

Also lay some groundwork needed to interactively change the
glitchfriend.

The codebase uses "elefriend" because it's shorter and didn't require me
to realign the actions in actions/compose.js.  Same idea, though.

Glitched elephant friends kindly provided by @ncls7615.