(PCP-213) Add test for file specs
(PCP-213) Add test for file specs

This commit adds an acceptance test to validate that the pxp-agent
installation conforms to the defined file layout specifications
as declared at
https://github.com/puppetlabs/puppet-specifications/blob/master/file_paths.md

puppetlabs/pxp-agent,puppetlabs/pxp-agent,puppetlabs/pxp-agent