phusion/passenger — pull request #1332 by richardkmichael (2014-12-23 05:40:28+00:00)
Title: Mention unattended-upgrades configuration.

The notation to add the Phusion APT repository to an unattended-upgrades configuration is not particularly obvious, so mention it in the installation documentation as an optional step.

Helpful discussion in Ubuntu forums: http://askubuntu.com/questions/64318/how-can-i-enable-silent-automatic-updates-for-google-chrome