add new class for failed around terminator

I did this because to get the around to fail in other tests
would cause the others to fail as well because they would all
raise and not save.
add test to test that ArgumentError is raised if no block

This test tests that an error is raised because this around
callback will fail. It also ensures that the message returned
is "no block given (yield)" to the user. It also tests that the
object is not saved.