Return proper http status codes on delete

BL/Interfaces/IFoorumService.cs

@@ -14,7 +14,7 @@ namespace BL.Interfaces
         FoorumDTO Add(FoorumDTO foorum);
         FoorumDTO Update(FoorumDTO foorum);
         void Hide(int id, bool hide=true);
-        void Delete(int id);
+        FoorumDTO Delete(int id);
         void AddPost(int id, PostDTO post);
 
         IEnumerable<FoorumDTO> SearchFoorumTitle(string query);