Update document index

Change-Id: I4d7719aec5e5b6d3ab3a23113c44267e1594ac2b

design/0002_governance_messaging.md

@@ -1,5 +1,7 @@
 # Cross-Chain Governance Decision Messaging
 
+[TOC]
+
 ## Objective
 
 Establish a protocol for wormhole core implementations and modules on different chains to communicate governance

design/navbar.md

@@ -1,8 +1,8 @@
 # Wormhole | Design Documents
 
 * [Generic Message Passing](./0001_generic_message_passing.md)
+* [Governance Messaging](./0002_governance_messaging.md)
 * [Token Bridge](./0003_token_bridge.md)
 * [Message Publishing](./0004_message_publishing.md)
-* [Staking](./0005_staking.md)
 
 [home]: ./navbar.md