Fixes races in test and klog (#3079)

Various fixes to make things less flaky:

* kubernetes: put klog.SetOutput in the setup function, not in the init
  function to see if that helps
* file: make z.Expired a boolean instead of a pointer to a boolean
* test: fix TestSecondaryZoneTransfer test, which wasn't actually
  testing in the right way. It's more right now, but may still be racy
  (race introduced because a file's lazy loading of zones)

Signed-off-by: Miek Gieben <miek@miek.nl>

plugin/file/file.go

@@ -72,7 +72,7 @@ func (f File) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (i
 	z.RLock()
 	exp := z.Expired
 	z.RUnlock()
-	if exp != nil && *exp {
+	if exp {
 		log.Errorf("Zone %s is expired", zone)
 		return dns.RcodeServerFailure, nil
 	}