postinstall script fails with yarn pkg manager

[hobbes7878]

Looks like yarn hangs on the input that is part of the package's postinstall script here.

Yarn did not always support postinstall scripts to begin with, but this may cause me to rethink keeping that script.

Still works great using npm, fwiw.

[hobbes7878]

Thinking now that maybe the better way to do this is to skip calling a postinstall script and instead write separate scripts that do the same asset moves per platform. Document how to run those from a path within node_modules, call it good.