INT 50 - Vanderaart TEXT WINDOWS - OUTPUT LINE TO WINDOW

	AX = 0003h
	ES:BX -> text string
	CX = string length (0000h if ASCIZ string)
	DL = position (FFh centered, else flush left)
	DH = starting row
	DI = window handle
Return: AX = status
	    0000h successful
	    FFFFh did not fit in window