never redirect from a redirect action

during testing, redirects may not be executed, ActionAbort can default
to redirecting which ould create an infinite loop.

inc/Action/Redirect.php

@@ -44,7 +44,7 @@ class Redirect extends AbstractAliasAction {
         trigger_event('ACTION_SHOW_REDIRECT', $opts, array($this, 'redirect'));
 
         // should never be reached
-        throw new ActionAbort();
+        throw new ActionAbort('show');
     }
 
     /**