Adding guidance and support for headers forwarding behind the proxy

[kdcllc]

• Configure ASP.NET Core to work with proxy servers and load balancers

• Forwarded Headers Middleware Updates in .NET Core 3.0 preview 6

{
  "KnownProxies": [
    "10.0.0.144"
  ]
}

services.Configure(options =>
{
      options.ForwardedHeaders = Microsoft.AspNetCore.HttpOverrides.ForwardedHeaders.All;

      foreach (var proxy in Configuration.GetSection("KnownProxies").AsEnumerable().Where(c => c.Value != null))
      {
           options.KnownProxies.Add(IPAddress.Parse(proxy.Value));
      }
});