add "run" to Command


    (dev2)# cat aa.py
    from terminal import Command, red

    def show(cmd):
        """
        foo's subcommand run

        :parms cmd: foo command
        """

        if cmd.color:
            print(red('show'))
        else:
            print('show')

    cmd_show = Command('show', 'show something', version='1.0.0', run=show)
    cmd_show.option('-c, --color', 'disable or enable colors')

    cmd_show2 = Command('show2', 'show2 something', version='1.0.1')
    cmd_show2.option('-c, --color', 'disable or enable colors')
    cmd_show2.run = show
    (dev2)#
    (dev2)# cat bb.py
    from terminal import Command
    from aa import cmd_show, cmd_show2

    program = Command('foo', version='1.0.0')
    program.action(cmd_show)
    program.action(cmd_show2)

    program.parse()
    (dev2)#
    (dev2)# python bb.py -h

      foo 1.0.0

      Usage: foo <command> [option]

      Options:

        -h, --help      output the help menu
        -V, --version   output the version number

      Commands:

        show            show something
        show2           show2 something

    (dev2)# python bb.py show
    show
    (dev2)# python bb.py show -c
    show
    (dev2)# python bb.py show2
    show
    (dev2)# python bb.py show2 -c
    show
    (dev2)#