(zone): Don't fiddle with the idle timer at all.
(zone-when-idle): Put the idle timer in zone-timer.
If one is already set up, cancel it and make a new one.
(zone-leave-me-alone): Likewise.
(zone-hiding-modeline): New macro.
(zone-call): New func.
(zone): Init `modeline-hidden-level' symbol property.
Use `zone-call' instead of `funcall'.
(zone-pgm-whack-chars): Use `make-string' (bug introduced in 2001-10-26T20:11:25Z!monnier@iro.umontreal.ca).
(zone-pgm-stress): Use `zone-hiding-modeline'.
(zone-pgm-stress-destress): New zone program.