Fix conditions for showing presence and payment on the event page

Ghost User
2018-07-05T10:39:35+02:00

Closes no issue (issue reported in the Thalia Whatsapp)

#### Previous behaviour
Steps to reproduce:

1. Create an event which requires registration.
2. Register and unregister for the event.
3. It still shows the payment status and presence.

#### New behaviour
Steps to validate that it works:

1. Create an event which requires registration.
2. Register and unregister for the event.
3. It no longer shows the payment status and presence.