debian ec2 fixes (mysql + php5)

* this fix contains noninteractive installation fixes for debian based system
* this fixes issues with the installation of unauthenticated packages under debian on EC2
* this fixes issues with the installation of MySQL under debian on EC2
* this fixes issues with the installation of PHP5 (and everything else relying on libc6) under debian on EC2

It will probably also help other debian software that pops up some nasty interactive configuration screen.