SLING-7167 Adjust READMEs

add uniform header linking to Sling project

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1810875 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/README.md b/README.md
index 63860da..2f2df07 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,5 @@
-Apache Sling Scripting HTL Compiler
-====
+# Apache Sling Scripting HTL Compiler
+
+This module is part of the [Apache Sling](https://sling.apache.org) project.
+
 The Apache Sling Scripting HTL Compiler provides support for compiling [HTML Template Language](https://github.com/Adobe-Marketing-Cloud/htl-spec) scripts into an Abstract Syntax Tree.