install use a subparser for install scripts

    '''

    Install an image

    '''

    # remove old image args

    args.parser._remove_action([d for d in args.parser._actions if d.dest == "image"][0])

    # create a subparser for current image to have a sexy display of args

    #args.image = "roger"

    subparser = args.parser.add_subparsers().add_parser(args.image)

    # select image to install

    repoman = load_repositories(args)

    img = select_image(args.image, repoman, args.best)[0]

    # add default show help options

    args.subparser.add_argument("-h", "--help", action="help", default=argparse.SUPPRESS,

                                help="show program's version number and exit")

    # Print setup information

    arrow("Installing %s v%s" % (img.name, img.version))

    # install start time

    t0 = time.time()

    # run parser scripts with parser parser argument

    img.run_parser(parser=args.subparser)

    img.run_parser(parser=subparser)

    # call parser again, with extended attributes

    arrow("Parsing arguments")

    args = parser.parse_args(namespace=args)

    #parser.print_help()

    args = parser.parse_args()

    # run setup scripts

    img.run_setup(namespace=args)

    # compute building time

p_install = subparsers.add_parser("install", add_help=False,

                                  help=c_install.__doc__.lower())

p_install.add_argument("-b", "--best", action="store_true", default=False,

                       help="in best mode, image is the most recent in all repositories")

                       help="take the most recent image in all searchable repositories")

p_install.add_argument("image",

                       help="image syntax is <path|[repository/]image[:version]>")

p_install.set_defaults(func=c_install, subparser=p_install)

p_install.set_defaults(func=c_install, parser=p_install)

# list command parser

p_list = subparsers.add_parser("list", help=c_list.__doc__.lower())

                    help="display image url")

p_list.add_argument("image", nargs="*", default=['*'],

                    help="image syntax is [repository/]image[:version]")

p_list.set_defaults(func=c_list, subparser=p_list)

p_list.set_defaults(func=c_list)

# move command parser

p_move = subparsers.add_parser("move", help=c_move.__doc__.lower())

p_version.set_defaults(func=c_version)

try:

    # Parse and run

    # first (partial) parsing

    args = p_main.parse_known_args()[0]

    # set debug and quiet mode before merge

    installsystems.debug = args.debug

    if args.no_color:

        installsystems.printer.NOCOLOR = True

    # except for install command we parse all args!

    # install command is responsible of parsing

    if args.func is not c_install:

        args = p_main.parse_args(namespace=args)

    # let's go