Function to check whether a member has filled in the addon information.
Some tests for the resources method "registrationDatesOf"
Method to check whether a participant registered at least a given number of days ago.
Management view for activities: Shows all members that did not pay / that did not fill in the addon information although they are registered for at least a week.
Merge pull request #671 from NicoleRauch/master

Added two new management views