Apt update tooling

This gives you the ability to have puppet run apt-get update a few different ways:

  * always
  * daily
  * weekly
  * reluctantly **default**

it determines when to trigger the apt-get exec via a combination of an addition of a script in apt.conf.d that touches a file when apt-get update runs, and a  custom fact which checks the mtime of that file.

all behavior should be covered by spec tests.

additionally fixed up the spec tests to function when running natively on non-debian systems

Please let me know if there are any changes you'd like to see here in order to merge this
Your comment above makes it sounds like this is intended to only run on Ubuntu, yet you confine to Debian? Is this right?