def initialize(args = ARGV)
      @args, @commands, @aliases, @options = args, {}, {}, []
      @help_formatter_aliases = help_formatter_alias_defaults
      @program = program_defaults
      @always_trace = false
      @never_trace = false
      create_default_commands
    end
#
Initialize a new command runner. Optionally
supplying _args_ for mocking, or arbitrary usage.