CC-3693: Uninstalling + Reinstall of Airtime + refreshing the page as a non-existant user causes a stack trace.

-Fixed

airtime_mvc/application/models/User.php

@@ -299,7 +299,14 @@ class Application_Model_User {
         if (is_null($userinfo)){
             return null;
         } else {
+            try {
                 return new self($userinfo->id);
+            } catch (Exception $e){
+                //we get here if $userinfo->id is defined, but doesn't exist
+                //in the database anymore.  
+                Zend_Auth::getInstance()->clearIdentity();
+                return null;
+            }
         }
     }
 }