I had to require('./astronomy.js') instead of require('astronomy.js')
to get the nodejs demos working, now that I maintain a redundant
copy of astronomy.js in the demo directories.
Windows does not support relative links in Git by default.
This broke the first-time experience for Windows users.
From now on I will maintain copies of the astronomy.js
and astronomy.py in the demo folders, so that the demos
will work on Windows immediately after cloning the repo.
