Specify charlock holmes version in installation docs

diff --git a/doc/installation.md b/doc/installation.md
index 524c8e8..5611c3b 100644 (file)
--- a/doc/installation.md
+++ b/doc/installation.md
@@ -134,7 +134,7 @@ Permissions:
 
 # 4. Install gitlab and configuration. Check status configuration.
 
-    sudo gem install charlock_holmes
+    sudo gem install charlock_holmes --version '0.6.8'
     sudo pip install pygments
     sudo gem install bundler
     cd /home/gitlab