added plugin parameter java signature

git-svn-id: https://svn.apache.org/repos/asf/maven/shared/trunk@1467735 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/src/site/apt/index.apt b/src/site/apt/index.apt
index 511b735..c809388 100644
--- a/src/site/apt/index.apt
+++ b/src/site/apt/index.apt
@@ -12,7 +12,8 @@
   {{{./apidocs/org/apache/maven/reporting/exec/MavenReportExecutor.html}MavenReportExecutor}}
   ({{{./apidocs/org/apache/maven/reporting/exec/DefaultMavenReportExecutor.html}implementation}}):
   report plugins can be configured in <<<\<configuration\>>>> element of <<<maven-site-plugin>>> or any other
-  report building plugin with following XML model:
+  report building plugin with following XML model corresponding to plugin's
+  <<<List<{{{./apidocs/org/apache/maven/reporting/exec/ReportPlugin.html}ReportPlugin}}>>>> parameter:
 
 +----+
 <reportPlugins>