headlamp-plugin: How to extract namespace packages so plugin folders?

[illume]

From https://github.com/kinvolk/headlamp/pull/643#discussion_r944270362

plugins/headlamp-plugin/bin/headlamp-plugin.js

    // @todo: should the whole package name be used here,
    //    and the load be fixed to use? What about namespace packages?

Good point. Maybe making the namespace as part of the target path? @kinvolk/podcounter-headlamp-plugin -> kinvolk-podcounter-headlamp-plugin?