IRS: Enable news feed (needs styling)
Disease: AddpersonWidget needs appropriate validator!
IRS: Use SL-specific hierarchy
Disease: Exposure (Contacts) should also use AddPersoNWidget, fix
AddResourceLink for Tracing
Disease: Tracing should be hidden on Contacts tab (& therefore not
mandatory)
Some business logic enhancements for contact tracing (WIP)
IRS: Enable Inv, Req, Projects
Fix too much recursion error during update_location_tree. Don't traverse descendents during the all-locations update. Actually disable update_location_tree during prepopulate. Add tests for update_location_tree.