Created Issue: Missing Assembly: Xceed.Wpf.Toolkit.Luna [19517]

I added Xceed Extended WPF Toolkit via Nuget and I get a "A first chance exception of type 'System.IO.FileNotFoundException' occurred in mscorlib.dll" which when I looked into it, found that it was looking for Xceed.Wpf.Toolkit.Luna.

Everything seems to work without this assembly.