Add note for using official released docker images

GitHub-Pr: https://github.com/GerritCodeReview/docker-gerrit/pull/22
Change-Id: Iab93ccec6361e55c64f87f72f33c800862e383d4
diff --git a/README.md b/README.md
index 094bad6..c53d68f 100644
--- a/README.md
+++ b/README.md
@@ -25,6 +25,12 @@
 Starting from Ver. 2.14, a new introduction screen guides you through the basics of Gerrit
 and allows installing additional plugins downloaded from [Gerrit CI](https://gerrit-ci.gerritforge.com).
 
+Official releases are also available as Docker images, e.g. use the following to run the 3.0.0 version.
+
+```
+docker run -ti -p 8080:8080 -p 29418:29418 gerritcodereview/gerrit:3.0.0
+```
+
 ## Build docker image
 
 For docker images that contain released Gerrit versions, tags exist in this git repository pointing