RoslynCompilationService should set the generated code when compilation is successful

Fixes #895
Enabling basic input formatter selection.

Conflicts:
	Mvc.sln
	src/Microsoft.AspNet.Mvc.Core/Formatters/TempInputFormatterProvider.cs
	src/Microsoft.AspNet.Mvc.Core/Microsoft.AspNet.Mvc.Core.kproj
	src/Microsoft.AspNet.Mvc.Core/ReflectedActionInvoker.cs
	src/Microsoft.AspNet.Mvc.Core/ReflectedActionInvokerProvider.cs
	src/Microsoft.AspNet.Mvc/MvcServices.cs
	test/Microsoft.AspNet.Mvc.Core.Test/Microsoft.AspNet.Mvc.Core.Test.kproj
	test/Microsoft.AspNet.Mvc.Core.Test/ReflectedActionInvokerTest.cs

Conflicts:
	src/Microsoft.AspNet.Mvc.Core/Formatters/TempInputFormatterProvider.cs