code: function _gpfGetFileExtension (mimeType) {
      var fileExtension = _gpfMimeTypesToExtension[mimeType.toLowerCase()];
      if (undefined === fileExtension) {
          // Default
          fileExtension = ".bin";
      }
      return fileExtension;
  }
docs: Retrieve the file extension associated with the mime type (default is ".bin")
  
  @param {String} mimeType
  @return {String}