[MSHARED-338] added documentation

git-svn-id: https://svn.apache.org/repos/asf/maven/shared/trunk@1601472 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/src/site/apt/index.apt.vm b/src/site/apt/index.apt.vm
index 48fef7c..3ea3b8d 100644
--- a/src/site/apt/index.apt.vm
+++ b/src/site/apt/index.apt.vm
@@ -75,6 +75,9 @@
 
   []
 
+  Since <<<maven-reporting-exec>>> 1.2 (which will be used by <<<maven-site-plugin>>> 3.4), plugin configuration in
+  <<<build/pluginManagement>>> is injected into reports.
+
   Maven 3 core makes an automatic transformation of <<<\<reporting\>>>> POM section (which supports configuration inheritance)
   to <<<maven-site-plugin>>>'s <<<reportPlugins>>> configuration through the
   {{{/ref/current/maven-model-builder/apidocs/org/apache/maven/model/plugin/ReportingConverter.html}ReportingConverter}}