RPI profile edit & update

[Jeddf]

Stage 2 task from Profile RPI migration epic CoderDojo/community-platform#1290

What

Create path for zen users to edit their linked my.raspberrypi profile.

Why

my.raspberrypi should be the only editing page for zen profile information that is not specific to zen.

How

• Add /rpi/edit endpoint that redirects to rpi profile edit page
• Add returnTo query param capablity to rpi profile edit page
• Have /rpi/login endpoint update stored zen user profile from rpi user profile if profileId is known
• If user session has profileId, serve zen edit profile page with a link to rpi edit profile and just the zen specific info available to edit.
• Redirect user to agree to terms and conditions after signup. (Require Accept Terms & Conditions #1392)
• in vue, cp-zen-frontend, watch for requiredFieldsComplete in logged in user and redirect to edit profile if false