Update stunnel to 4.39.

component/stunnel/buildout.cfg

@@ -17,8 +17,8 @@ filename = stunnel-4-hooks.py
 
 [stunnel-4]
 recipe = hexagonit.recipe.cmmi
-url = ftp://ftp.stunnel.org/stunnel/stunnel-4.38.tar.gz
-md5sum = de5c0478303da746f946d9c112fa7f4b
+url = ftp://ftp.stunnel.org/stunnel/stunnel-4.39.tar.gz
+md5sum = 853739119a8364daea750154af6d7e79
 pre-configure-hook = ${stunnel-4-hook-download:location}/${stunnel-4-hook-download:filename}:pre_configure_hook
 configure-options =
   --enable-ipv6