/// <summary>
 /// Add a new contact.
 /// </summary>
 /// <param name="contact">Contact to add.</param>
 /// <returns>The added contact</returns>
 public HttpResponseMessage Post(Contact contact)
 {
     if (this.ModelState.IsValid)
     {
         bool issuccess = contactStore.Post(contact);
         if (issuccess)
         {
             return(Request.CreateResponse <Contact>(HttpStatusCode.Created, contact));
         }
     }
     return(Request.CreateResponse(HttpStatusCode.BadRequest));
 }