Fix log message on http handler error

Signed-off-by: Alexandr Morozov <lk4d4math@gmail.com>

api/server/server.go

@@ -1058,7 +1058,7 @@ func makeHttpHandler(eng *engine.Engine, logging bool, localMethod string, local
 		}
 
 		if err := handlerFunc(eng, version, w, r, mux.Vars(r)); err != nil {
-			utils.Errorf("Error making handler: %s", err)
+			utils.Errorf("Handler for %s %s returned error: %s", localMethod, localRoute, err)
 			httpError(w, err)
 		}
 	}