Prior to this commit, install stripped out all instance of lib,
which was fine, but now we are vendoring code for facts, and we
need that directory to exist for the vendored so that the require
is correct and because that directory contains the license.
Prior to Facter 2.0, we weren't vendoring code that specifically
required a license, so we didn't need to propagate licenses. Now
Facter 2.0 is vendoring code and we need to explicitly include
the license for that code.