Add INT option for deleted_at

Author: MGatner

user_guide_src/source/models/model.rst

@@ -144,9 +144,9 @@ can maintain a "recycle bin" of objects that can be restored, or even simply pre
 part of a security trail. If true, the find* methods will only return non-deleted rows, unless
 the withDeleted() method is called prior to calling the find* method.
 
-This requires a DATETIME field to be present in the table for storing state. The default field
-name is  ``deleted_at`` however this name can be configured to any name of your choice by using
-$deletedField property.
+This requires requires either a DATETIME or INTEGER field in the database as per the model's
+$dateFormat setting. The default field name is ``deleted_at`` however this name can be
+configured to any name of your choice by using $deletedField property.
 
 **$allowedFields**