NAME:
       rdimg
PURPOSE:
       Read and return the two images in an old style MaxEnt map.
CATEGORY:
  File I/O
CALLING SEQUENCE:
       rdimg('myfile.dat',pluto,charon)
INPUTS:
       filename = string containing the name of the file to read.
OUTPUTS:
       pluto    = First image in file, usually Pluto.
       charon   = Second image in file, usually Charon.
REVISION HISTORY:
       Written by Marc Buie on 10/21/91
COMMENTS: