JSON properties now lower case on swap from ASP .Net Core 1.0.0-rc2-final to 1.0.0

MVC now serializes JSON with camel case names by default

Use this code to avoid camel case names by default

  services.AddMvc()
        .AddJsonOptions(options => options.SerializerSettings.ContractResolver = new DefaultContractResolver());

Source:
https://github.com/aspnet/Announcements/issues/194