Allow immutable date times

Author: TNAJanssen

lib/Gedmo/SoftDeleteable/Mapping/Validator.php

@@ -22,9 +22,13 @@ class Validator
      */
     public static $validTypes = array(
         'date',
+        'date_immutable',
         'time',
+        'time_immutable',
         'datetime',
+        'datetime_immutable',
         'datetimetz',
+        'datetimetz_immutable',
         'timestamp',
         'zenddate',
     );