Add screenshot to each subdirectory within Demos

[oliveroxtoby]

In GitLab by @david.yoga on Sep 6, 2022, 15:04

It would be excellent if the in each Demos/../README.md there would be an attached screenshot of the demo itself (i.e. before and after images)

[oliveroxtoby]

In GitLab by @oliveroxtoby on Sep 6, 2022, 19:52

I guess that would be helpful. I'm looking forward to your pull request! :P

[icojb25]

@oliveroxtoby I guess there are a couple more images to add, not covered in the PR above, so we should keep this open for the meantime