Orphaned Listings fix

[highnote]

If a user is deleted from the admin console, any listings that user had created remain in the database and are then "orphaned" and there is no real way to search for them.

To fix this, I wrote a little function to delete all user's listings during a user_delete.
I have attached a zip file with the file here.  The modified file is  /system/modules/users/admin/functions/edit_users.php

Changes are in lines 94-102 and the new function is at the top called: delete_user_listings()
There is perhaps a more elegant way to search for all the listings for a user, but this way worked based on my unit testing.
Please review and let me know if you see any issues in the code.
Regards,
Lou