INT 21,16 - Create a File Using FCB

	AH = 16h
	DS:DX = pointer to an unopened FCB

	on return:
	AL = 00 if file created
	   = FF if file creation failed

	- creates file using FCB and leaves open for later output
	- FCB must be setup with drive id, filename, and extension
	  before call
	- an extended FCB can be used to also set file attributes