Improved RequireHttpsHandler to automatically redirect the caller if applicable and provide a link to where the requested resource can be found.

Based on this blog post: http://blogs.msdn.com/b/carlosfigueira/archive/2012/03/09/implementing-requirehttps-with-asp-net-web-api.aspx, but implemented as a DelegatingHandler as this check should happen as early in the pipeline as possible.