C#/DevKit code under Compiler Symbol don't get ignored (go gray) if not used

* Compiler symbols that are not in use don't have the code under them gray.
* Intellisense also continues to work to work in these disabled code blocks when it shouldn't.
* Also maybe this is due to no UI options allowing us to toggle between difference build configurations?

I was testing this with a Unity3D project. These are called "Scripting Define Symbols" in Unity.
In short this can make parsing code a little annoying.