Serialize json attribute names in lower case

LowercaseContractResolver.cs

public class LowerCasePropertyNamesContractResolver : DefaultContractResolver
{
    protected override string ResolvePropertyName(string propertyName) => propertyName.ToLowerInvariant();
}

Startup.cs

public class Startup
{
    public void Configuration(IAppBuilder app)
    {
        var config = new HttpConfiguration();

        config.Formatters.JsonFormatter.SerializerSettings.ContractResolver = new LowerCasePropertyNamesContractResolver();
    }
}