Updated Contributing (markdown)

Contributing.md

@@ -4,5 +4,7 @@ If you'd like to contribute to the Fluid Framework open source codebase, first o
 
 We have tried to make it as easy as possible to set up your local clone of the Fluid Framework so that you can hit the ground running. Let's get started!
 
-* [Repo Basics](https://github.com/microsoft/FluidFramework/wiki/Repo-Basics)
-* [Building and Running](https://github.com/microsoft/FluidFramework/wiki/Building-and-Running)
+  * [Repo Basics](https://github.com/microsoft/FluidFramework/wiki/Repo-Basics)
+  * [Client Code](https://github.com/microsoft/FluidFramework/wiki/Client)
+  * [Server Code](https://github.com/microsoft/FluidFramework/wiki/Server)
+  * [PR Guidelines](https://github.com/microsoft/FluidFramework/wiki/PR-Guidelines)