code: function startSites(config){
          config.siteNames.forEach(function(item){
              var cmd = 'iisexpress /site:"'  + item + '"';
  
              if(config.configFile !== ""){
                  cmd += ' /config:"' + config.configFile + '"';
              }
  
              if (config.sysTray){
                  cmd += ' /systray:true';
              }else{
                  cmd += ' /systray:false';
              }
  
              gulp.src('')
                  .pipe(shell([
                      cmd
                  ],{
                      cwd: config.iisExpressPath
                  }))
                  .on('error', util.log);
          });
  
          return gulp.src('');
      }
docs: starting the sites.