Added the Tips module to Showdown.Nancy

Set up the routing in the module and the front end code for navigation.
Some parts need tidying up, especially user feedback.
Added the Review and Restaurent Module.

Added fully qualified namespace in therazor views, to enable intellisense.
Added the routes to the Review and Restaurant module.

Made changes to the views.
changes to the model, restaurant has a review and not the other way around.