parser: Make config file parser more hierarchy

pass 'state' down the stack so that the state of the
hierarchy doesn't get lost when there are unexpected items
in the config hierarchy.

Don't bother setting 'state' on SECTION_END as there's no point
now we're going back up the stack.

Signed-off-by: Christine Caulfield <ccaulfie@redhat.com>
Reviewed-by: Jan Friesse <jfriesse@redhat.com>