Update readme.md

readme.md

@@ -8,10 +8,10 @@ A Docker base-image containing Ruby dependencies for Jekyll instances using Jeky
 | 0.1 (or legacy)   |   Jekyll 3.8.6 | 1.17.3          |
 
 # How to use?
-In your `.gitlab-ci.yml` file add the following line:
+In your `.gitlab-ci.yml` file add the following line (make sure `r3` is written in lower-case):
 
 ```
-image: git-r3lab.uni.lu:4567/R3/docker/baseimage-jekyll-lcsb:latest
+image: git-r3lab.uni.lu:4567/r3/docker/baseimage-jekyll-lcsb:latest
 ```
 
 # How to build and push to the repository?