Added svg mime type and github action

[rpeyron]

Hello,

Thanks for your updates on miniweb. This is a very small PR to add SVG mime type and a GitHub action to build Windows version, and some doc on both subjects as I may be useful for other people.

Best regards

[avih]

Thanks.

I'll keep this issue open for posterity, but as the message at the readme and the project page says:

This project is not maintained, and should not be considered secure.