DOC: mention lighttpd 1.4.46 implements PROXY

lighttpd 1.4.46 implements PROXY v1 and v2 for incoming connections.
diff --git a/doc/proxy-protocol.txt b/doc/proxy-protocol.txt
index 358bce0..4969180 100644
--- a/doc/proxy-protocol.txt
+++ b/doc/proxy-protocol.txt
@@ -724,6 +724,9 @@
 
 Jetty 9.3.0 supports protocol version 1.
 
+lighttpd added support for versions 1 and 2 of the protocol for incoming
+connections in version 1.4.46 [11].
+
 The protocol is simple enough that it is expected that other implementations
 will appear, especially in environments such as SMTP, IMAP, FTP, RDP where the
 client's address is an important piece of information for the server and some
@@ -913,6 +916,7 @@
 [8] https://tools.ietf.org/html/rfc4960#appendix-B
 [9] https://tools.ietf.org/rfc/rfc7301.txt
 [10] https://www.ietf.org/rfc/rfc3546.txt
+[11] https://redmine.lighttpd.net/issues/2804
 
 9. Sample code