Should explain how to theme images

[flywhc]

themes are not only about color but also about images. Dark mode usually has many different images from Light mode for example.

Xamarin does have support images for dark mode on iOS and Android but no documents explain them. I did google and found a good article to explain how to do a theme with a complete solution. This should be done by Microsoft officials. https://intelliabb.com/2019/11/02/how-to-support-dark-mode-in-xamarin-forms/

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Document Details

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• ID: 3f353ff4-2d18-218c-f0d5-b3110e476c4d
• Version Independent ID: a1cec8f2-969c-23c5-a252-b417afcacff6
• Content: Theme a Xamarin.Forms Application - Xamarin
• Content Source: docs/xamarin-forms/user-interface/theming/theming.md
• Product: xamarin
• Technology: xamarin-forms
• GitHub Login: @davidbritch
• Microsoft Alias: dabritch