doc improvement.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@23340 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/PluginManager.java

@@ -441,6 +441,9 @@ public final class PluginManager extends AbstractModelObject {
         }
     }
 
+    /**
+     * {@link ClassLoader} that can see all plugins.
+     */
     private final class UberClassLoader extends ClassLoader {
         public UberClassLoader() {
             super(PluginManager.class.getClassLoader());