Event looks like registered for though on waiting list

One-sentence description

When on the waiting list for an event, it still looks like you are registered for that event.

Current behaviour / Reproducing the bug

• In the calendar stream, the event does appear in your calendar
• Cancelling your registration does show the warning that you have to pay a fine, if after the unregistration deadline
• In the event overview calendar, the dot in front of the event is colored as if you are registered.

Expected behaviour

• Do not appear in the calendar stream
• Do not show a message that you cannot unregister without having to pay a fine, but something different more fit to the situation
• In the event overview, show some other, pending-ish, colored dot.