constructors.  There is no backward compatibility.  Not everything has
  been tested.
* aiff.{py,doc}: deleted in favor of aifc.py (which contains its docs as
  comments)

* mainloop.py: don't use select unless absolutely necessary (for Mac)

* Fixed calendar.py, mimetools.py, whrandom.py to cope with time.time()
  returning a floating point number.  (And fix old bug in calendar)
* Add recursion level to mainloop.mainloop(), to make it reentrant.

* Many modules: fixes for new, stricter, argument passing rules
  (most changes were automatic ones -- not all of this is tested!).
* gwin.py: now uses mainloop.py for its main loop and window admin.
* mainloop.py: always call dispatch() with event as a tuple!
* Fix bug in pdb's 'clear' command -- don't set the bpt but clear it!

  embryonic facility for pseudo-modal dialogs.
* stdwinevents.py: added modifier masks for key/mouse events
* renamed exceptions in nntplib.py
* Changed string.join() to call string.joinfields() to profit of
  strop.joinfields()