SLING-3912 add link to Sling Scripting Thymeleaf documentation

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1625944 13f79535-47bb-0310-9956-ffa450edef68
SLING-3912 add link to Sling Scripting Thymeleaf documentation

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1625945 13f79535-47bb-0310-9956-ffa450edef68