Sorted dict 1

Pull request for SortedDict and BalancedTree23 taking into account Kevin Squire's feedback from the past 12 days.
> Is this correct? If so, should I include similar code in SortedDict when an item is deleted from the structure?

Yes, that is correct.  Tough call.  I'm a little leary, but I don't think these will disappear from `Base` any time soon, and they are being used for the same reason.

How about using them, but adding a test to see if the call succeeds (just create an array and call the function on it).  If the test ever fails, we'll know that those calls would need to change.