admin: panels can install additional url rules
babel: jinja needs deferredJS extension
views: add JSONView
JS: remove loadScript. i18n files loading is done directly in base template

loadScript was not the right way to go: the following script tags was
executed despite insertion of new scripts before, which lead to curious
bugs at least under firefox.

 The kind of bug that never happens when debugger is enabled since the
added script are loaded during that time.
admin audit panel: add day selector, filter by user, filter by content type