Merge branch 'master' into glitch-soc/merge-upstream

Conflicts:
- `Gemfile.lock`:
  No real conflict, glitch-soc-only dependency (redcarpet) too close to an
  upstream one (rdf-normalize)
- `README.md`:
  we have different READMEs, discarded upstream's changes
- `app/views/admin/custom_emojis/index.html.haml`:
  No real conflict, different context because of glitch-soc theming
- `lib/mastodon/statuses_cli.rb`:
  Upstream added code to keep bookmarked statuses, we were already doing so
  with slightly different code. Discarded upstream's changes.
- `package.json`:
  No real conflict, glitch-soc-only dependency (favico.js) too close to
  an upstream one

app/javascript/mastodon/locales/en.json

@@ -1,6 +1,7 @@
 {
   "account.add_or_remove_from_list": "Add or Remove from lists",
   "account.badges.bot": "Bot",
+  "account.badges.group": "Group",
   "account.block": "Block @{name}",
   "account.block_domain": "Hide everything from {domain}",
   "account.blocked": "Blocked",
@@ -87,6 +88,8 @@
   "compose_form.poll.duration": "Poll duration",
   "compose_form.poll.option_placeholder": "Choice {number}",
   "compose_form.poll.remove_option": "Remove this choice",
+  "compose_form.poll.switch_to_multiple": "Change poll to allow multiple choices",
+  "compose_form.poll.switch_to_single": "Change poll to allow for a single choice",
   "compose_form.publish": "Toot",
   "compose_form.publish_loud": "{publish}!",
   "compose_form.sensitive.hide": "Mark media as sensitive",