On the neverending search for using c#6 features in unity I recently stumbled over a small repository.
This project allows you - with small modifications of unity - to use the Roslyn-Compiler-Platform and with it huge amounts of fancy c#5 and c#6 features in Unity.

I'm someone living on the bl...

I've played a bit with alexzzzz C#6 Support for Unity and found that there was one essential thing missing: A class extending MonoBehaviour providing access to several async method similar to Xenkos SyncScript and AsyncScript.