Plugin documentation: Linkify multiple and root SSH commands

Change-Id: Id0076e9a5b97981abe7240dc94a2802264deaa17
diff --git a/Documentation/dev-plugins.txt b/Documentation/dev-plugins.txt
index 2e9c83c..1cdb8fd 100644
--- a/Documentation/dev-plugins.txt
+++ b/Documentation/dev-plugins.txt
@@ -494,6 +494,9 @@
 $ ssh -p 29418 review.example.com helloworld print
 ----
 
+[[multiple-commands]]
+=== Multiple Commands bound to one implementation
+
 Multiple SSH commands can be bound to the same implementation class. For
 example a Gerrit Shell plugin can bind different shell commands to the same
 implementation class:
@@ -532,6 +535,9 @@
 $ ssh -p 29418 review.example.com shell ps
 ----
 
+[[root-level-commands]]
+=== Root Level Commands
+
 Single command plugins are also supported. In this scenario plugin binds
 SSH command to its own name. `SshModule` must inherit from
 `SingleCommandPluginModule` class: