Added parameter to enable Unicorn to listen on given IP address

Why should Unicorn listen on non-localhost IP?

Because on my environment there is a bare metal server with a reverse proxy and Gitlab runs on a virtual machines.

So I have to enable Unicorn to listen on the virtual lan IP to be reached by the reverse proxy.

Having 2 reverse proxies, one on the physical an one on the vm, looks like a waste of resources to me.
Notice: /Stage[main]/Gitlab::Install/Gitlab::Config::Unicorn[gitlab]/File[/srv/git/gitlab/config/unicorn.rb]/content:
--- /srv/git/gitlab/config/unicorn.rb   2014-10-30 10:17:37.808915999 +0100
+++ /tmp/puppet-file20141030-32056-1nkkpsh      2014-10-30 11:00:40.360915999 +0100
@@ -42,7 +42,7 @@
 # listen on both a Unix domain socket and a TCP port,
 # we use a shorter backlog for quicker failover when busy
 listen "/srv/git/gitlab/tmp/sockets/gitlab.socket", :backlog => 64
-listen "0.0.0.0:8080", :tcp_nopush => true
+listen "127.0.0.1:8080", :tcp_nopush => true

 # nuke workers after 30 seconds instead of 60 seconds (the default)
 timeout 300

This is what happens on my env if gitlab_unicorn_listen is commented out...
I can't figure out why travis is so sad :(