added a link to the Jellydoc

core/src/site/markdown/index.md

+Collection of Maven auto-generated reports. The primary interest is probably [Jelly tag libary reference](jelly-taglib-ref.html).

pom.xml

@@ -505,6 +505,13 @@ THE SOFTWARE.
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-site-plugin</artifactId>
           <version>3.0</version>
+          <dependencies>
+            <dependency>
+              <groupId>org.kohsuke</groupId>
+              <artifactId>doxia-module-markdown</artifactId>
+              <version>1.0</version>
+            </dependency>
+          </dependencies>
         </plugin>
         <!--This plugin's configuration is used to store Eclipse m2e settings only. It has no influence on the Maven build itself.-->
         <plugin>