User Should Be Able to Delete Their Accounts (2)

[fny]

We need to add a button that allows a user to delete their accounts entirely.

The button should be on the settings page.

This should call on a DELETE /v1/users/:user_id. This endpoint should delete the user and all associated information in the app.

TODO: Additional details need to be discussed with the team. We may need to collect anonymous usage information for the charities we work with, and data usage agreements may differ from location to location.