code: function (callback) {
        return this._request({
          path: this._extension
        }, function (err, body, res) {
          return err
            ? callback(err)
            : callback(null, body.networks, res);
        });
      }
docs: client.getNetworks
  
  @description Display the currently available networks
  
  @param {Function}    callback    f(err, networks) where networks is an array of networks
  @returns {*}