Change title Breaking ties with stable sorting

[bnmnetp]

When I read that title I thought the section was going to be about non-stable sorting. Perhaps it would be clearer to title the section Stable Sorting breaks ties predictably ??

[presnick]

New title will be "Breaking Ties: Second Sorting".

Show them how to make the key function return a tuple and explain that tuple sorting is always first element, then second element to break ties.