INT 2F - SWELL.EXE - INSTALLATION CHECK                                         
	AX = CD00h
Return: AX = 00FFh installed
	    BH = major version
	    BL = minor version
Program: SWELL.EXE is a TSR(Terminate and Stay Resident) A program which remains in memory after terminating in order to provide services to other programs or the user.  The name comes from the name of the DOS function call used to remain in memory after termination. which swaps programs to disk when they EXEC a
	  child process with INT 21/AH=4Bh