This PR adds a new notification cleaning mode, super perfectly tuned for accessibility, and removes the previous notification cleaning functionality as it's now redundant.

* w.i.p. notif clearing mode

* Better CSS for selected notification and shorter text if Stretch is off

* wip for rebase ~

* all working in notif clearing mode, except the actual removal

* bulk delete route for piggo

* cleaning + refactor. endpoint gives 422 for some reason

* formatting

* use the right route

* fix broken destroy_multiple

* load more notifs after succ cleaning

* satisfy eslint

* Removed CSS for the old notif delete button

* Tabindex=0 is mandatory

In order to make it possible to tab to this element you must have tab index = 0. Removing this violates WCAG and makes it impossible to use the interface without good eyesight and a mouse. So nobody with certain mobility impairments, vision impairments, or brain injuries would be able to use this feature if you don't have tabindex=0

* Corrected aria-label

Previous label implied a different behavior from what actually happens

* aria role localization & made the overlay behave like a checkbox

* checkboxes css and better contrast

* color tuning for the notif overlay

* fanceh checkboxes etc and nice backgrounds

* SHUT UP TRAVIS

* Added DELETE verb for notifications

* Added notification dismiss button to status dropdown

* Added reveal-on-hover notif dismiss button, added FollowNotification component

* Add semi to ESLint rules

* Add padded-blocks to ESLint rules

* Add comma-dangle to ESLint rules

* add config/webpack and storyboard

* add streaming/

* yarn test:lint -- --fix

* Replace browserify with webpack

* Add react-intl-translations-manager

* Do not minify in development, add offline-plugin for ServiceWorker background cache updates

* Adjust tests and dependencies

* Fix production deployments

* Fix tests

* More optimizations

* Improve travis cache for npm stuff

* Re-run travis

* Add back support for custom.scss as before

* Remove offline-plugin and babili

* Fix issue with Immutable.List().unshift(...values) not working as expected

* Make travis load schema instead of running all migrations in sequence

* Fix missing React import in WarningContainer. Optimize rendering performance by using ImmutablePureComponent instead of
React.PureComponent. ImmutablePureComponent uses Immutable.is() to compare props. Replace dynamic callback bindings in
<UI />

* Add react definitions to places that use JSX

* Add Procfile.dev for running rails, webpack and streaming API at the same time