platform_family-ization

handles RHEL5/RHEL6 and should handle RHEL7 correctly (as long as it is RHEL6-like) and uses platform_family to catch all current and future RHEL variants correctly.  it even handles current versions of xenserver, fedora and amazon, along with all the debian flavors (chef-server on raspbian...).  it does not handle old xenserver/fedora/amazon version that are RHEL5-like.