Added uwp sample for Todolist

[AutumnEvans418]

Added a UWP sample for the todo sample:

The event log logger provider in Microsoft extensions is not implemented for UWP and will throw an exception if you run the app, so I updated the app to remove that logger:

  .ConfigureLogging(d =>
                {
                    d.ClearProviders();
                    d.AddConsole();
                })

This was the only change I had to make for UWP to work.

[dnfclas]

All CLA requirements met.

[Eilon]

Very cool, I will take a look at this!