Updating Microsoft.AspNet.Mvc.Core.Test to work on Mono

This brings up an interesting point though, AF depends on ClaimsIdentity and not IIdentity, which means it would not be able to support generic identity @GrabYourPitchforks, should we have anti forgery depend on IIdentity instead of ClaimsIdentity? I still see HttpContext.User.Identity as IIdentity @Tratcher do we intend to change it to claims identity sometime?