Demo Reference Update

I've updated the references to the PHP Variant demos to point to the new Azure deployment of the site.

The main index-eng.html and index-fra.html files point directly to the demos site, but I've also updated the php/index-eng.html and php/index-fra.html files so people with bookmarks won't end up with a 404 if we were to removed the php/index-xxx.html pages altogether or by being pointed to the older RCMP demos deployment.