main.rb features the following:
    - unification of option, argument, keyword, and environment
      parameter parsing
    - auto generation of usage and help messages
    - support for mode/sub-commands
    - io redirection support
    - logging hooks using ruby's built-in logging mechanism
    - intelligent error handling and exit codes
    - use as dsl or library for building Main objects
    - parsing user defined ARGV and ENV
    - zero requirements for understanding the obtuse apis of any
      command line option parsers
    - leather pants

  In short main.rb aims to drastically lower the barrier to writing
  uniform command line applications.
