Upgrade caddy to 0.11.X (#2541)

* Upgrade caddy to 0.11.2

Redo of #2505 (cherry-picked commit)
Signed-off-by: Miek Gieben <miek@miek.nl>

* .4 has been released
Signed-off-by: Miek Gieben <miek@miek.nl>

Makefile

@@ -31,7 +31,7 @@ godeps:
 	go get -u github.com/miekg/dns
 	go get -u github.com/prometheus/client_golang/prometheus/promhttp
 	go get -u github.com/prometheus/client_golang/prometheus
-	(cd $(GOPATH)/src/github.com/mholt/caddy              && git checkout -q v0.11.1)
+	(cd $(GOPATH)/src/github.com/mholt/caddy              && git checkout -q v0.11.4)
 	(cd $(GOPATH)/src/github.com/miekg/dns                && git checkout -q v1.1.4)
 	(cd $(GOPATH)/src/github.com/prometheus/client_golang && git checkout -q v0.9.1)
 

core/dnsserver/server.go

@@ -142,6 +142,11 @@ func (s *Server) Listen() (net.Listener, error) {
 	return l, nil
 }
 
+// WrapListener Listen implements caddy.GracefulServer interface.
+func (s *Server) WrapListener(ln net.Listener) net.Listener {
+	return ln
+}
+
 // ListenPacket implements caddy.UDPServer interface.
 func (s *Server) ListenPacket() (net.PacketConn, error) {
 	p, err := listenPacket("udp", s.Addr[len(transport.DNS+"://"):])