Development take place on the SWT branch, which automatically detects your oprating system. In order to publish your changes, you need to merge them onto the win64,lin64 and mac64 branches.
If the Jitpack cache won't pick up your changes, you can trigger a build with the exact commit hash like: https://jitpack.io/com/github/baloise/proxy/04d893f57df5716619df1eaa02585e02be7980b6/proxy-04d893f57df5716619df1eaa02585e02be7980b6.jar
To generate png from svg run mvn -Pdownload-svg2png to download the jar.
This is a work around for https://github.com/sterlp/svg2png/issues/20 and only and only needs to be done once.
Then to transform the svgs to pngs run mvn -Psvg2png