BZ #1038281 - Do not disable selinux on openstack foreman installer.

https://bugzilla.redhat.com/show_bug.cgi?id=1038281
BZ #1038772 - Remove Tech Preview text

https://bugzilla.redhat.com/show_bug.cgi?id=1038772
Merge pull request #70 from jguiditta/bz1038281_selinux

Bz1038281 selinux