Support SVG image

This works!

Patch do not work anymore in 1.0.1, I updated it.

This patch decorative_image_widget-support-SvgImageWidget-1.0.1.patch works in 1.0.1 for me.

SvgImage now inherits from ImageWidget so the patch might not be needed anymore.

I gave a try to version 1.0.2 and the problem persists.

I confirm that the patch works with version 1.0.1 but it must be updated to work with 1.0.2

Here's a version that works with 1.0.2

Tried again with svg_image 3.2.1 and decorative_image_widget 1.0.2 and I can't reproduce anymore.
Probably fixed by 🐛 Why is SvgImageWidget inheriting from FileWidget instead for ImageWidget? Active as @mably said.