Call with `make -f makefile_web` to produce a web root for serving. Use
target "boids_web_root.tar" to bundle the files into a tarball. For...
publishing... or something.
The `wasm-server-runner` program seems to supply it's own index.html and
is doing *something* regarding MIME types -- hosting a dev build of the
Boids program results in the browser complaining about "" (empty string)
being an invalid MIME type.
I want my own index.html during testing, and I can't figure out why the
MIME type info is wrong. I've decided to automate the web-root build
process and serve it up with whatever webserver I have on hand.
