* Fix Doorkeeper error

* use Doorkeeper::OAuth::Scopes.from_string

* Basic onboarding modal that's shown to users once

* Lay out pages 2 through 5, add images, style modals (#1509)

* Lay out pages 2 through 5

Added images and laid out pages 2 through 5 in the jsx file. SCSS will
come, still working on just seeing if this works at all.

* Fix jsx errors, add images to modal pages, style modal pages

* Add animations to onboarding pager changes, improve wording and styling

* Finishing touches on the onboarding

* Add missing propTypes

* Update wording

An attempt to open a brand new Mastodon instance configured
as SINGLE_USER_MODE=true will cause an exception.

Enable temporary registration if we have no users in the database

Fixes #1817

to the API

registration API

Adding better errors for the API controllers, posting a simple status works from the frontend now

a basic home timeline