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

Conflicts:
	README.md
	app/controllers/statuses_controller.rb
	app/lib/feed_manager.rb
	config/navigation.rb
	spec/lib/feed_manager_spec.rb

Conflicts were resolved by taking both versions for each change.
This means the two filter systems (glitch-soc's keyword mutes and tootsuite's
custom filters) are in place, which will be changed in a follow-up commit.

config/navigation.rb

@@ -23,6 +23,7 @@ SimpleNavigation::Configuration.run do |navigation|
       end
     end
 
+    primary.item :filters, safe_join([fa_icon('filter fw'), t('filters.index.title')]), filters_path, highlights_on: %r{/filters}
     primary.item :invites, safe_join([fa_icon('user-plus fw'), t('invites.title')]), invites_path, if: proc { Setting.min_invite_role == 'user' }
 
     primary.item :development, safe_join([fa_icon('code fw'), t('settings.development')]), settings_applications_url do |development|