Allow groups to be archived as an alternative to deleting them.

Many of the things we utilize student groups for are unique to a season (eg graduating seniors each year). Some groups can be deleted, but others (like having a list of alumni who graduated in a certain year) would be nice to reference in subsequent seasons. The student and class groups are a great feature, but now my list of groups is very long. I would love the option to archive groups rather than only delete them, so we can keep these records without having such a long list of groups to choose from every time I need to utilize that function!