Fixing style issues in Mvc.Core
activate line length rule
Introducing ChallengeResult to call Response.Challenge()
Issue #65 merge RoutingContext and RequestContext

See the relevant PR in aspnet/Routing#60.

This incorporates the breaking changes.
changing to use list instead of stack
fix a build break due to api change
setting line length to 120 to match our guidelines
fixing stylecop in .Mvc and .Mvc.Common