Update manual installation guide for the correct shell version.

doc/install/installation.md

@@ -257,7 +257,7 @@ We recommend using a PostgreSQL database. For MySQL check [MySQL setup guide](da
 GitLab Shell is an SSH access and repository management software developed specially for GitLab.
 
     # Run the installation task for gitlab-shell (replace `REDIS_URL` if needed):
-    sudo -u git -H bundle exec rake gitlab:shell:install[v1.9.7] REDIS_URL=redis://localhost:6379 RAILS_ENV=production
+    sudo -u git -H bundle exec rake gitlab:shell:install[v2.0.0] REDIS_URL=unix:/var/run/redis/redis.sock RAILS_ENV=production
 
     # By default, the gitlab-shell config is generated from your main GitLab config.
     # You can review (and modify) the gitlab-shell config as follows:

doc/update/upgrader.md

@@ -47,12 +47,12 @@ If all items are green, then congratulations upgrade is complete!
 
 If the `gitlab:check` task reports an outdated version of `gitlab-shell` you should upgrade it.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 1.9.4 with the correct version number:
+Upgrade it by running the commands below after replacing 2.0.0 with the correct version number:
 
 ```
 cd /home/git/gitlab-shell
 sudo -u git -H git fetch
-sudo -u git -H git checkout v1.9.4
+sudo -u git -H git checkout v2.0.0
 ```
 
 ## One line upgrade command