exclude README.md in rat report

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1732095 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/pom.xml b/pom.xml
index 9b655ca..2cb378d 100644
--- a/pom.xml
+++ b/pom.xml
@@ -155,6 +155,7 @@
                         <excludes combine.children="append">
                             <!-- Exclude sling instance -->
                             <exclude>sling/**</exclude>
+                            <exclude>README.md</exclude>
                         </excludes>
                     </configuration>
                 </plugin>