add SHOW command
add WINDOW
add AUTOSOLVE
add GOTO prompt, GOTOF, GOTOTR
add special GOTO commands: MAINMENU/MTASKMENU/GOPRODUCT/GOSTORAGE/EXIT
add SYSCALL and RCOND
add < comparison operator
add data model commands (a bit confusing)
add AddressOrValue for data model commands
fix parsing of data model arguments
hmmmmm