Move the diffdict utility function to the utilities module.
Test fix for fullname, which is no longer a strictly computed value.
Test fix for a now mutable fullname where we were testing for read-only access to non-mutable values. Changed to _legacy_id because this is a newly added non-mutable value that won't be going away anytime soon.
Fixes tests where the user attribute 'lastname' was changed to 'surname'.
Fixes the User's 'lastname' to 'surname' attribute change in the view code. All tests pass.
Fixes instance identity check for security.Allowed and security.ACLAllowed. Fixes #6
Correct the misspelled variable name.