public ActivityEnvelope(ActivityViewModel model)
 {
     Activity = new Activity();
     Activity.Action = model.Activity_Action;
     Activity.Actor.Name = model.Actor_Name;
     Activity.Actor.Email = model.Actor_Email;
     Activity.Message = model.Activity_Message;
     Activity.OG_Object.Title = model.Object_Title;
     Activity.OG_Object.Url = model.Object_Url;
 }
 public ActivityEnvelope()
 {
     Activity = new Activity();
 }