// Called e.g. as /authorize?response_type=code&client_id=testclient&state=f00bar&scope=email&redirect_uri=http%3A%2F%2Ffake.example.com%2F
// This either redirects to the redirect URL with errors or success added as GET parameters,
// or sends a HTML page asking for login / permission to scope (email is always granted in this system but not always for OAuth2 generically)
// Called e.g. as /authorize?response_type=code&client_id=testclient&state=f00bar&scope=email&redirect_uri=http%3A%2F%2Ffake.example.com%2F
// This either redirects to the redirect URL with errors or success added as GET parameters,
// or sends a HTML page asking for login / permission to scope (email is always granted in this system but not always for OAuth2 generically)