User profile: Subscribe checkbox

[Torniojaws]

In the user page, there should be a checkbox which toggles subscribing to important news. The user can also unsubscribe via a link in the email, but that is a separate ticket.

• [ ] Add a checkbox in the UI: [ ] Subscribe to important news, such as new album releases, entering the studio, new live shows or events.
• [ ] The checkbox sends a POST /api/1.0/subscribers and the user will then start to get future notifications via Email
• [ ] When the user page is opened, it sends a GET /api/1.0/users/:id which should contain the flag whether the user is already a subscriber or not. If already a subscriber, the checkbox will be checked automatically.
• [ ] Unchecking the box will unsubscribe, ie. sends a DELETE /api/1.0/subscribers

[Torniojaws]

It's possible the user does not have an email. Should check they do. If not, should show a message "Please add your email to the profile"