add support for varnish 4
Thanks, works great for me.
@espebra says he'll have a look and merge it if it works as announced :-)
Thanks! @evgeni, did you test this on Ubuntu 12.04?
@espebra: only on Debian Wheezy (Varnish 3) and Debian Sid (Varnish 4)
Compiles and works. Thanks, @evgeni.