Send user a message when not able to convert category icon #20
Description
With the completion of issue #5 we are still not able to auto generate a decayimage for a category icon if it is not a PNG. We also have no way of alerting the user because we do not have access to the application/controllers/admin/manage.php file in a way that we can add errors. We could either add a 'pre' event to application/controllers/admin/manage.php or we can implement our own small view that will create a popup message.