INT 10 - VIDEO - TELETYPE OUTPUT

	AH = 0Eh
	AL = character to write
	BH = page number
	BL = foreground color (graphics modes only)
Return: nothing
Desc:	display a character on the screen, advancing the cursor and scrolling
	  the screen as necessary
Notes:	characters 07h (BEL), 08h (BS), 0Ah (LF), and 0Dh (CR) are interpreted
	  and do the expected things
	IBM PC ROMs dated 1981/4/24 and 1981/10/19 require that BH be the same
	  as the current active page
BUG:	if the write causes the screen to scroll, BP is destroyed by BIOSes
	  for which AH=06h destroys BP
SeeAlso: AH=02h,AH=06h,AH=0Ah