Description - Provide a way on Project Templates at the Project / Task and Issue levels to limit which users can be assigned. Could be done by setting a "Select Users from..." and allow the project owner / template owner to select groups, teams, users, or access levels
Why is this feature important to you - Some teams are assigning work to people who do not actually do the work
How would you like the feature to work - Act in similar way to using the Typeahead Filter
Current Behaviour - Anyone can actually be assigned
