SIMP should use reboot notify for SELinux reboot requirements

When SELinux is disabled, and a user requests that it be set to either permissive or enforcing, a resulting Puppet error occurs because it attempts to run 'setenforce'.

Instead, this should check to see the state of SELinux on the system itself, and if a reboot is required to properly use the setenforce command, the reboot_notify type should be used instead of allowing a failed resource to execute.