title: pass relative url in signalR hub connection
body: <p>I am trying to implement signalR in angularJS, 
  I want to pass relative url to hub connection, but it's making current url (on which my angular application is hosted)</p>
  
  <p>My API base url : <code>http://localhost:81/NrsService/api/TestSignal</code></p>
  
  <p>My angular application running at </p>
  
  <pre><code>http://localhost:81
  </code></pre>
  
  <p>Here is my signalR setup :</p>
  
  <pre><code>$.connection.hub.url = "/NrsService/api/TestSignal";
  //Getting the connection object
  connection = $.hubConnection();
  </code></pre>
  
  <p>Like it is sending request at  <code>http://localhost:81/signalr/negotiate?</code> but I want it to be  <code>http://localhost:81/NrsService/api/TestSignal/negotiate?</code></p>