Patch, originally from Bastian Kleineidam and savagely mutilated by me,

to add the "display metadata" options: --name, --version, --author,
and so forth.  Main changes:
  * added 'display_options' class attribute to list all the "display only"
    options (--help-commands plus the metadata options)
  * added DistributionMetadata class as a place to put the actual
    metadata information from the setup script (not to be confused with
    the metadata display options); the logic dealing with metadata
    (eg. return self.name or "UNKNOWN") is now  in this class
  * changed 'parse_command_line()' to use the new OO interface provided
    by fancy_getopt, mainly so we can get at the original order of
    options on the command line, so we can print multiple lines of
    distribution meta-data in the order specified by the user
  * added 'handle_display_options()' to handle display-only options
Also fixed some crufty old comments/docstrings.