Merge branch 'add-new-gitlab-shell' of /home/git/repositories/gitlab/gitlabhq into 6-2-stable

doc/install/installation.md

@@ -122,7 +122,7 @@ GitLab Shell is an ssh access and repository management software developed speci
     cd gitlab-shell
 
     # switch to right version
-    sudo -u git -H git checkout v1.7.4
+    sudo -u git -H git checkout v1.7.9
 
     sudo -u git -H cp config.yml.example config.yml