Add page to personal tab administration views showing list of former members with unsettled balances

[Kurocon]

Split from #1039

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Next to that, I am thinking about a separate tab in the Treasurer Personal Tab environment in which former members with a non-zero balance are written down. To find these 50 people I had to manually check per person with a negative balance if they were still a member or not, so a separate tab would be very useful.

[Kurocon]

Discussed with Lars, this is a wanted feature and is very feasible to implement.