code: function HttpClient(connectionConfig)
  {
    // save the connection config
    this._connectionConfig = connectionConfig;
  
    // check that we have a valid request module
    var requestModule = this.getRequestModule();
    Errors.assertInternal(
        Util.isObject(requestModule) || Util.isFunction(requestModule));
  }
docs: Creates a new HTTP client.
  
  @param connectionConfig
  @constructor