Show principal_type in acl list for unusual types
Show principal_type in acl list for unusual types

For anonymous and all_authenticated_users we want to show the type, not
the value, in the acl listing. (The values for these are always "").
Luckily, the other values in this column fit strict formats that
preclude any matches with these strings, so the result is unambiguous.

Resolves #114

globus/globus-cli,globus/globus-cli