Comment 8 for bug 1155769

Thanks Kyle! Picked your commit to master and then backported to rel_2_5. When I tried to backport it to rel_2_4, it didn't pick cleanly and there seem to be differences in how sort worked previously in 2.4. Specifically, that the label_sortkey wasn't being employed and also that copy_number wasn't being used either.

Going to leave that 2.4 stuff alone for now. Maybe can look at it more closely later.