Tell customers to request hooks.

doc/git_hooks/git_hooks.md

@@ -8,6 +8,9 @@ GitLab Enterprise Edition offers a user-friendly interface for such cases.
 Git hooks are defined per project so you can have different rules applied to different projects depends on your needs.
 Git hooks settings can be found at Project settings -> Git Hooks page.
 
+## New hooks
+
+If you are a subscriber and need a hook that is not there yet we would be glad to add it for free, please contact support to request one.
 
 ## How to use