Document that port 8000 must be used for lineman reloading

[nilbus]

Using port 4567, I couldn't figure out why my JS wouldn't reload with lineman building things for me. Hopefully this will help others later who hit the same problem.

[kotp]

Can someone verify this is indeed a requirement for this specific port number? A reference perhaps? It feels to me that it should be configurable to match whatever rackup is set up to.

[nilbus]

It seems to be convention, documented all over docs/setting-up-local-development.md, and hard-coded in the lineman config, frontend/config/application.coffee.

[nilbus]

docker-compose.yml also uses 4567, consistent with everything else.

That's not to say it couldn't be changed, but the default rackup port and default puma port aren't the same.

[kytrinyx]

Thanks, @nilbus.