pprint functions used to sort a dict (by key) if and only if

pprint functions used to sort a dict (by key) if and only if
the output required more than one line.  "Small" dicts got
displayed in seemingly random order (the hash-induced order
produced by dict.__repr__).  None of this was documented.
Now pprint functions always sort dicts by key, and the docs
promise it.

This was proposed and agreed to during the PyCon 2006 core
sprint -- I just didn't have time for it before now.