Unbound dhcpd

o Add $waitforit flag to killbypid() and use it to simplify code.

o When requesting a configure via id, do not exclude the service
  because it is disabled.  The pidfile needs to be killed still.

o Unwind the convoluted code paths in the VPN plugin during early
  configure: kill service, probe for active, then do work.

This will make a few good people very happy.  :)

(legacy) refactor services_unbound_acls.php, add automatically generated acl's. closes https://github.com/opnsense/core/issues/563

(proxy) set unset description on X-Forwarded-For. closes https://github.com/opnsense/core/issues/790