Add installation of squid(3)

Signed-off-by: Robert Einsle <robert@einsle.de>
Adding configuration for automatically updates of debian-packages

Signed-off-by: Robert Einsle <robert@einsle.de>
Adding Documentation of squid-module

Signed-off-by: Robert Einsle <robert@einsle.de>
Adding debian-module for managing sources.list

Signed-off-by: Robert Einsle <robert@einsle.de>