Merge branch 'automate-upgrader-shell-version' into 'master'

Automate upgrader shell version

/cc @marin

See merge request !1237

doc/update/upgrader.md

@@ -43,28 +43,31 @@ Check if GitLab and its dependencies are configured correctly:
 If all items are green, then congratulations upgrade is complete!
-## 5. Upgrade GitLab Shell (if needed)
-If the `gitlab:check` task reports an outdated version of `gitlab-shell` you should upgrade it.
-
-Upgrade it by running the commands below after replacing 2.0.1 with the correct version number:
+## 5. Upgrade GitLab Shell
+GitLab Shell might be outdated, running the commands below ensures you're using a compatible version:
 ```
 cd /home/git/gitlab-shell
 sudo -u git -H git fetch
-sudo -u git -H git checkout v2.0.1
+sudo -u git -H git checkout v`cat /home/git/gitlab/GITLAB_SHELL_VERSION`
 ```
 ## One line upgrade command
 You've read through the entire guide and probably already did all the steps one by one.
-Here is a one line command with step 1 to 4 for the next time you upgrade:
+Here is a one line command with step 1 to 5 for the next time you upgrade:
 ```bash
-cd /home/git/gitlab; sudo -u git -H bundle exec rake gitlab:backup:create RAILS_ENV=production; \
+cd /home/git/gitlab; \
+  sudo -u git -H bundle exec rake gitlab:backup:create RAILS_ENV=production; \
   sudo service gitlab stop; \
   if [ -f bin/upgrade.rb ]; then sudo -u git -H ruby bin/upgrade.rb -y; else sudo -u git -H ruby script/upgrade.rb -y; fi; \
+  cd /home/git/gitlab-shell; \
+  sudo -u git -H git fetch; \
+  sudo -u git -H git checkout v`cat /home/git/gitlab/GITLAB_SHELL_VERSION`; \
+  cd /home/git/gitlab; \
   sudo service gitlab start; \
   sudo service nginx restart; sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production
 ```