Displays the planet, coproom, hospital, and home for each zone. Zones which share a common 'fwd' attribute are shown on the same line.

example:
  >planets
  Planet                Cop room       Hospital          Saves Zones
  ^YLivingstone^n          lstone_72      lstone_44       lstone_7 ^Zlstone, bingo, enozon, grail, linmouth, ocean, orange, retired, rsf, tea, wilderness, wstone

see also:
  $[zones$], $[objects$], $[rooms$], $[mobiles$], $[mobjects$]
