Adding table of contents to docs longer than ~one page.

Change-Id: I3bb3afe88e5c54a3fdbed32a0a0dace1b65e85ee
diff --git a/docs/StyleGuide.md b/docs/StyleGuide.md
index 9422df8..300e34c 100644
--- a/docs/StyleGuide.md
+++ b/docs/StyleGuide.md
@@ -15,6 +15,8 @@
 tooling conflicts with what is in this document we accept what the tooling
 requires, and try to improve it if possible.
 
+[TOC]
+
 ## Clarifications
 
 *   Yes, it does mean all variables are declared, C90-style, at the top of