Advice developers to use shorter and nicer IValueConvert syntax instead of old WPF-style

[maxkatz6]

Topics to cover

Many developers don't like IValueConverters because of their verbosity.
They need to create an instance of a class, implement two-way methods, add it to the resources, and so on.

Instead, we should let them know that it's possible to use converters with x:Static and FuncValueConverter.
Simple examples:

public static class IntConverters
{
    public static FuncValueConverter<int, bool> IsNotZero { get; } = new(i => i != 0);
}

<Image Grid.Column="0" Source="/Assets/checkmark.png" Width="28" Height="28"
       IsVisible="{Binding Value.Count, Converter={x:Static converters:IntConverters.IsNotZero}}" />

That's it.

I haven't checked our documentation and all samples. But in general, that's what we can recommend for one-way IValueConverter and IMultiValueConverter. Additionally, we should add FuncValueConverter two-way conversion support.