MENU : Displays menu with choices shown as multiple branches to different
locations within the program.
syntax: MENU("<title>", "<text1>", <label1>, "<text2>", <label2>, ...)
MENU sets up branching within a program. If MENU is encountered during
execution, the menu screen is displayed with the specified menu items, and
execution pauses until a menu selection is made. The menu <title> is enclosed
in quotes " as well as the text description for each <label>.