Ask for email opt in

[mvexel]

Upon first signing in to MapRoulette, can we ask for an email opt in? In the future we may want to send out periodic emails. This should be optional and settable in application configuration (for internal deploys we'd never need it)

The text would be:

"Are you OK with receiving the occasional email from MapRoulette? (You can opt out of this at any time.)"

Then also the user settings should have an email opt in checkbox.

[reichg]

Is the email opt in in the user settings sufficient for this?