docs: def cmd_version(unused_conf):
      """Print out version information about YABT and detected builders."""
      import pkg_resources
      print('This is {} version {}, imported from {}'
            .format(__oneliner__, __version__, __file__))
      if len(Plugin.builders) > 0:
          print('setuptools registered builders:')
      for entry_point in pkg_resources.iter_entry_points('yabt.builders'):
          print('  {0.module_name}.{0.name} (dist {0.dist})'.format(entry_point))