INT 13 u - QUICKCACHE II v4.20 - DISMOUNT                                       
	AH = 20h
	AL = drive (00h = A:, etc. or 7Fh for all removable drives???
				   or FFh for all drives)
Return: AX = status (0000h successful)
Program: QUICKCACHE II is a shareware disk cache by P.R. Glassel and
	  Associates, Inc.
Desc:	flush any dirty buffers for the specified drive(s) and then discard
	  those sector buffers
SeeAlso: AH=21h"QUICKCACHE",AH=22h"QUICKCACHE",AH=28h