Reduce Webpack memory usage

[davidmehren]

The current webpack config uses about 5 GB of memory to minify our JS. That seems a bit excessive for the few MBs of JS we have.

We should look into optimzing that, probably by excluding things that are already minified (librarys etc.).

See https://webpack.js.org/configuration/optimization/

[sibelius]

did you figure it out?

[ambyjkl]

might as well ditch webpack now for newer and better alternatives i guess, though it would be some hard work