Merge branch 'pages-mount-point-check' into 'master'

Check mountpoint for gitlab-pages

This prevents to start GitLab Pages daemon before actual mount exist.

Actually the `mountpoint` should be an array of mounts, because as for GitLab.com we have 5 different mountpoints, but we check only a one.

cc @marin 

See merge request !777

files/gitlab-cookbooks/gitlab/templates/default/sv-gitlab-pages-run.erb

@@ -4,6 +4,8 @@ set -e # fail on errors
 # Redirect stderr -> stdout
 exec 2>&1
 
+<%= render("mount_point_check.erb") %>
+
 cd <%= node['gitlab']['gitlab-pages']['dir'] %>
 
 exec /opt/gitlab/embedded/bin/gitlab-pages \