long_format():  Easy speedup for output bases that aren't a power of 2 (in particular, str(long) and repr(long) use base 10, and that gets a factor of 4 speedup).  Another factor of 2 can be gotten by refactoring divrem1 to support in-place division, but that started getting messy so I'm leaving that out.
long_format():  Easy speedup for output bases that aren't a power of 2 (in
particular, str(long) and repr(long) use base 10, and that gets a factor
of 4 speedup).  Another factor of 2 can be gotten by refactoring divrem1 to
support in-place division, but that started getting messy so I'm leaving
that out.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator