Ephemeral Storage

Hi Henrik,

This is a clone of your ephemeral branch.  I've played with it to test VM contextualization for ATLAS and Belle2.  It's been very useful thus far!  The two commits below are ment to address: a few syntax errors in the code we brainstormed for the ephemeral storage, and how the new version of facter treats custom facts.

For the second I've gone back to our discussion from October 7 and 8.  Unfortunately facter currently does not support boolean values.  The only data structure for a fact is a string, see

http://projects.puppetlabs.com/issues/4561

Apparently this is will be in facter version 2.  Hence I've defaulted back to using osvariant (to avoid statements like is_cernvm == "true", which just look confusing to me).  What do you think?

Cheers,
-Frank