Scale Bar - Example Gallery

[kolibril13]

Hi @ppinard!
I've just written an example gallery for the matplotlib-scalebar package:
https://kolibril13.github.io/plywood-gallery-matplotlib-scalebar/
One can click on one image and the corresponding code will be displayed.
Feedback is welcome!
What do you think about mentioning this gallery in the readme?

[ppinard]

Thank you for the contribution and apologies for not merging the PR sooner.