SLING-7167 Adjust READMEs

add uniform header linking to Sling project

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1810923 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/README.md b/README.md
index 50d48ec..65a9a2e 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,6 @@
-Apache Sling - Scripting - W3C XML Processing Support
+# Apache Sling Scripting W3C XML Processing Support
+
+This module is part of the [Apache Sling](https://sling.apache.org) project.
 
 Support for pipelines based on W3C XML Processing.
 (See http://www.w3.org/TR/xproc/)