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

Conflicts:
- README.md
  discarded upstream changes
- app/controllers/api/v1/bookmarks_controller.rb
  finally merged upstream, some code style fixes
  and slightly changed pagination code
- app/controllers/application_controller.rb
  changed upstream to always return HTML error pages
  slight conflict caused by theming code
- app/models/bookmark.rb
  finally merged upstream, no real conflict
- spec/controllers/api/v1/bookmarks_controller_spec.rb
  finally merged upstream, slightly changed pagination code

app/models/bookmark.rb

@@ -3,11 +3,11 @@
 #
 # Table name: bookmarks
 #
-#  id         :bigint(8)        not null, primary key
-#  account_id :bigint(8)        not null
-#  status_id  :bigint(8)        not null
+#  id         :integer          not null, primary key
 #  created_at :datetime         not null
 #  updated_at :datetime         not null
+#  account_id :integer          not null
+#  status_id  :integer          not null
 #
 
 class Bookmark < ApplicationRecord