MailChimp integration is broken

[cdriehuys]

Bug Report

Our current implementation of the MailChimp integration is broken. The biggest issue is that when registering, a user is saved before their email address is created. When the integration tries to look up the user's email address, we get an error.

To fix the integration, it should probably be tied to email instances instead of users.

[cdriehuys]

Tying the integration to emails instead of users would result in each user possibly being subscribed multiple times. We just need to check for the existence of their primary email address before we use it.

[cdriehuys]

Whoops, managed to misunderstand my own comment...

The integration's signal should definitely be tied to the saving of email addresses rather than users.