added IApi::getChangingElements()

#13

Author: gregor-j

src/Api/IApi.php

@@ -38,6 +38,12 @@ public function getInputElements(): array;
      */
     public function getOutputElements(): array;
 
+    /**
+     * Get all direction changing elements of the remote function.
+     * @return IApiElement[]
+     */
+    public function getChangingElements(): array;
+
     /**
      * Get all tables of the remote function.
      * @return IApiElement[]