Allow instance admins to add custom CSS that will affect
every page of their instance.
This is done with a new CustomCSS instance setting that
works pretty much exactly like the Users CustomCSS property.
This custom CSS is then requested for every page load.
User styles/themes take precedence over this CSS.
* [chore] Refactor HTML templates and CSS
* eslint
* ignore "Local"
* rss tests
* fiddle with OG just a tiny bit
* dick around with polls a bit more so SR stops saying "clickable"
* remove break
* oh lord
* don't lazy load avatar
* fix ogmeta tests
* clean up some cruft
* catch remaining calls to c.HTML
* fix error rendering + stack overflow in tag
* allow templating attributes
* fix indent
* set aria-hidden on status complementary content, since it's already present in the label anyway
* tidy up templating calls a little
* try to make styling a bit more consistent + readable
* fix up some remaining CSS issues
* fix up reports