fieldalignment of all structs to save memory

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

server/subscriber.go

@@ -28,19 +28,19 @@ var (
 )
 
 type handler struct {
-	method  reflect.Value
 	reqType reflect.Type
 	ctxType reflect.Type
+	method  reflect.Value
 }
 
 type subscriber struct {
-	topic      string
-	rcvr       reflect.Value
+	opts       SubscriberOptions
 	typ        reflect.Type
 	subscriber interface{}
+	rcvr       reflect.Value
+	topic      string
 	handlers   []*handler
 	endpoints  []*register.Endpoint
-	opts       SubscriberOptions
 }
 
 // Is this an exported - upper case - name?