code: function gulpServeIISExpress(config){
          // Config object...
          if (!config) {
              throw new util.PluginError(PLUGIN_NAME, "Config is missing!");
          }
  
          // configFile...
          if (!config.configFile) {
              config.configFile = "";
          }
  
          // siteNames...
          if (!config.siteNames) {
              config.siteNames = [];
          }
  
          // appPath...
          if (!config.appPath) {
              config.appPath = "";
          }
  
          // port...
          if (!config.port) {
              config.port = 8080;
          }
  
          // clrVersion...
          if (!config.clrVersion) {
              config.clrVersion = "v4.0";
          }
  
          if (config.configFile != "" && config.appPath != "") {
              throw new util.PluginError(PLUGIN_NAME, "Cannot combine config file-based IIS Express run with path-based run");
          }
  
          if (config.appPath == "" && config.siteNames.length == 0) {
              throw new util.PluginError(PLUGIN_NAME, "No sites to run in config");
          }
  
          // Config sysTray...
          if (!config.sysTray) {
              config.sysTray = true;
          }
  
          if(!config.iisExpressPath || config.iisExpressPath == ""){
              config.iisExpressPath = process.env.PROGRAMFILES + "\\IIS Express";
          }
  
          // Return by starting the sites.
          return gulp.src('/index.html')
              .pipe(startSites(config))
              .on('error', util.log);
      }
docs: main gulp plugin function ------------------------- PARAMS config: object contains the following: configFile - path to the config file. siteNames - array of site names. appPath - application folder path. port - port number to serve the application. Defaults to 8080. clrVersion - Version of clr. sysTray - Show the application in the system tray. iisExpressPath - Path to IIS Express if different from programfiles (x86)