v0.21.3

• It's now possible to generate a URI that completely takes a developer through the setup process for creating an OAuth2 client, with all values pre-filled. This makes it very easy for a developer to get their environment up and running without having to know all kinds of OAuth2 details (@AminDhouib).
• Fixed getting no feedback after changing group members. (@AminDhouib)
• Fixed the 'authenticated-as' link in the a12n-server home document; it had an extra slash.
• If you hit an authenticated page after login, you are now redirected back to that page after login.
• The /register endpoint can now take a ?continue= uri parameter, making it possible to redirect back to any application after registering.