Update get_selinux_facts in setup module
Update get_selinux_facts in setup module

This switches to using selinux library calls instead of parsing the
output of sestatus.  This fixes issue #428 where the output was slightly
different than expected on F17.  Tested against debian (non-selinux),
centos5, centos6, and fedora17.

thaim/ansible,thaim/ansible