Allow Users to Merge Accounts

[danielBingham]

Story Description

What are we trying to accomplish in plain english?

We could find ourselves in a situation where users have created multiple accounts with different emails (personal, institutional, etc). We need to provide a way for them to merge their accounts into a single account. This is particular relevant if they later choose to attach their orcid ID, because we'll find all of their accounts if they have their emails on their ORCID record.

Acceptance Criteria

At what point is this story considered "done"?

• When we discover users with multiple accounts we notify them and allow them to merge them.
• The merge screen lets them choose which account will be the new account.
• Merging moves all of their relationships into the main account, with the main account overriding any conflicts.

Dependencies

What stories does this one depend on? What do we need to do first before we can call this one done?

This depends on #93 .