Upgrading SignalR and RavenDB to the latest versions + getting WinRT up and running
Merge branch 'RemovingHolderClasses' of https://github.com/dolittle/Bifrost into RemovingHolderClasses

Conflicts:
	Source/Bifrost.RavenDB/Events/EventStore.cs
Removed explicitly using Newtonsoft for Converters
Fixed what is identified as SignalR internal types
Getting the WinRT version to compile - CurrentPrinipal will throw a not implemented exception - so we'll need to revisit this
Updating nuget