fix -- the order of searching for relation handlers, at first search …

…in registered handlers, then try to check instance of base relations

src/Domain/Relation/RelationHandlerResolver.php

@@ -17,6 +17,15 @@ public function __construct(){
 
     public function make( $relation ): RelationHandler
     {
+        // at first search in registered handlers, user can register his own handlers
+        $relationClass = get_class($relation);
+
+        if($this->handlers->has($relationClass))
+        {
+            return $this->handlers->get($relationClass);
+        }
+
+        // then try to check is relation has instance of base relations
         $handler = $this->handlers->first(function (RelationHandler $handler) use ($relation){
             $handlerRelation = $handler->relation();
             return $relation instanceof $handlerRelation;
@@ -27,6 +36,7 @@ public function make( $relation ): RelationHandler
             return $handler;
         }
 
+        // oops, not registered relation
         throw new DomainException(sprintf('RelationHandler for relation: %s is not registered', $relation));
     }