Use the haproxy source balance method.

* modules/cgit/manifests/init.pp: HTTP(S) access to the git cluster may
end up making connections to different node members potentially causing
fetches to fail when a ref is visible on one node but not on another.
Fix this by using the source balance method. Every request from a single
host will be served by one backend node unless nodes are added or
removed.

Change-Id: Iedca1938277020b837eb1607e43013f5feb2ed2d

modules/cgit/manifests/init.pp

@@ -238,6 +238,7 @@ class cgit(
       mode             => 'tcp',
       collect_exported => false,
       options          => {
+        'balance' => 'source',
         'option'  => [
           'tcplog',
         ],
@@ -249,6 +250,7 @@ class cgit(
       mode             => 'tcp',
       collect_exported => false,
       options          => {
+        'balance' => 'source',
         'option'  => [
           'tcplog',
         ],
@@ -262,6 +264,7 @@ class cgit(
       options          => {
         'maxconn' => '32',
         'backlog' => '64',
+        'balance' => 'source',
         'option'  => [
           'tcplog',
         ],