DOC - General IRAF Documentation

    expressions - Standard expression syntax in IRAF tasks
        pmmatch - Pixel mask matching

       -- Old Historical Documents --
       biblio84 - Summary of IRAF documentation (circa 1984)
         crib83 - Cribsheet for the Program Interface (circa 1983)
	  pkg84 - Package structure (circa 1984
	  spp83 - SPP reference manual (circa 1984)