INT 2F - DR DOS 6.0 TaskMAX - ENABLE/DISABLE DIRECT SWITCHING                   
	AX = 2705h
	DL = subfunction
	    00h disable keystrokes for switching to next/prev/specified task
	    01h enable
Return: nothing
Note:	should only be called by a registered task manager (see AX=2704h)
SeeAlso: AX=2704h,AX=2706h