Updated NuGet-Packages to current version:

Moq 4.1.1311.0615
Microsoft.Owin 2.0.2
Microsoft.Owin.Diagnostics 2.0.2
Microsoft.Owin.Host.HttpListener 2.0.2
Microsoft.Owin.Hosting 2.0.2
Microsoft.Owin.Security 2.0.2