docs: function _preCommand(commands) {
    commander.on('--help', function () {
  
      var hasExample = _.map(_.values(commands), 'examples')
        .filter(function (elem) {
          return elem !== undefined;
        });
      if (hasExample.length > 0) {
        hasExample = hasExample.reduce(function (a, b) {
          return a.concat(b);
        });
      }
      hasExample = hasExample.length > 0;
  
      if (hasExample) {
  
        console.log('  Examples:\n');
  
        Object.keys(commands).forEach(function (command) {
          if (!_.isEmpty(commands[command].examples)) {
            console.log('    %s:', command);
            commands[command].examples.forEach(function (example) {
              console.log('      %s', example);
            });
          }
        });
      }
    });
  }