docs: function Redmine(host, config, port) {
    if (!host) throw new Error('host not specified!');
  
    if (typeof host === 'string') {
      host = Url.parse(host);
    } else if (typeof host !== 'object') {
      throw new Error('host should be a string or url object!');
    }
    if (port) {
      host.port = port;
      host.host += ':' + port.toString();
    }
  
    var baseUrl = Url.format(host);
    this._request = request.defaults({baseUrl: baseUrl});
  
    if (!config || !(config.apiKey || (config.username && config.password))) {
      throw new Error('You should provide an API key or username & password !');
    }
    this.config = config;
  }