Added link to apache2.4 doc

Author: Chluz

web-server/apache/gitlab-apache2.4.conf

@@ -11,6 +11,8 @@
   ProxyPreserveHost On
 
   <Location />
+    # New authorization commands for apache 2.4 and up
+    # http://httpd.apache.org/docs/2.4/upgrading.html#access
     Require all granted
 
     ProxyPassReverse http://127.0.0.1:8080