Added Dictionary<string, object> as a source type for the DataProxy class

I apologize if this isn't the best code, it's not for lack of trying. The DataProxy class is pretty sweet when working with actual pages to retain the user's values. However, DataProxy was designed to work with DAL objects, not Lasy's Dictionaries. I also added a test for my change. Additionally, I added the .nuget folder so that Nvelope can find the Nvelope.Reactive packages that it needs automatically.