Update TOC

Author: Matt Pryor

docs/book/src/clusteropenstack/configuration.md

@@ -14,7 +14,8 @@
 - [Optional Configuration](#optional-configuration)
   - [Log level](#log-level)
   - [External network](#external-network)
-  - [Floating IP](#floating-ip)
+  - [API server floating IP](#api-server-floating-ip)
+    - [Disabling the API server floating IP](#disabling-the-api-server-floating-ip)
   - [Network Filters](#network-filters)
   - [Multiple Networks](#multiple-networks)
   - [Subnet Filters](#subnet-filters)