Reworded the user checker aliases explanation

javiereguiluz · xabbuh · commit de34b77db4e3 · 2017-01-10T20:48:18.000+01:00
diff --git a/security/user_checkers.rst b/security/user_checkers.rst
@@ -211,8 +211,3 @@ It's possible to have a different user checker per firewall.
                 ),
             ),
         ));
-
-.. note::
-
-    Internally the user checkers are aliased per firewall. For ``secured_area``
-    the alias ``security.user_checker.secured_area`` would point to ``app.user_checker``.
