Lego_setup [Ca trace Y/N] [colour ramp] [main chain database] [database directory] [rotamer database]
Define necessary parameters for the menu. This allows the user to select an option to show or not show CA traces, the colour codes to be used to display them, a file with the definition of the precalculated CA diagonal distance matrix, the directory where this database is kept and the file with the side chain rotamer database. Most of the values will be correct by default, but it is necessary to define these parameters the first time the Lego commands are used with a given database file.