code: function writeHTMLFile(options) {
    return new Promise(function(resolve, reject) {
      var templateFile = path.join(__dirname, '../template/cli.html');
       // read our template file
       fs.readFile(templateFile, 'utf8', function (err,data) {
        if (err) {
          reject(err);
        }
        // insert the generated json data
        var result = data.replace('{{ insertJSONHere }}', 'var embeddedJsonData = '+ options.json + ';');
  
        // write file to directory
        fs.writeFile(path.join(options.directory, 'index.html'), result, 'utf8', function (err) {
           if (err) {
            reject(err);
           }
           resolve(options.directory);
        });
      });
    });
  }
docs: This method creates index.html with injected data.
  
  @param  {Object}  options            Options data
  @param  {String}  options.directory  Directory
  @param  {Object}  options.json       JSON data.
  @return {void}