coreos/etcd — pull request #315 by GeertJohan (2013-11-19 10:05:37+00:00)
Title: Add symlink for etcd to /usr/local/bin

This way, running the image with a custom entrypoint doesn't require the full cmd path (`/opt/etcd/etcd`), which a user must first look up in this Dockerfile. I believe being able to directly call the binary is pretty much standard for docker images.