Display information about unsubscribed members (if they had submitted addon-information and/or payment)
Test for activity.memberIdsOfAddons()
grouped general addon tests into their own describe.
Extracting the addon lines for unsubscribed members that have addon or payment info and displaying them on the management page.
Merge pull request #742 from NicoleRauch/master

Display unsubscribed participants that have addon or payment information.