Unicornopoly: The Fast-Dealing Property Trading Game... (Update Property fluent API to match design meeting notes)

This change updates the Property method to match the design meeting notes from https://github.com/aspnet/EntityFramework/wiki/Entity-Framework-Design-Meeting-Notes-June-5,-2014#fluent-api

Specificly:
- Remove shadow state and concurreny parameters and add fluent methods instead
- Make string overloads create shadow properties by default unless the property is already known