Util\Translator: tell us current locale and lang
layout: add lang to HTML element
authentication/login: add missing alt tag
ActionController: allow to disable autorefresh
ActionController: refine url handling on redirect
helpers/widget: options are opional
JS/XHR: handle multiple notifications

As there seems to be problems with sending the same header multiple
times we put multiple notifications in one header.
JS/XHR: last commit was missing the JS part