Consider adding a linter / some static analysis about sbt-extras

[dwijnand]

• http://jvns.ca/blog/2017/03/26/bash-quirks/

[dwijnand]

ghcup runs shellcheck like so:

edo()
{
	printf "\\033[0;34m%s\\033[0m\\n" "$*" 1>&2
    "$@" || exit 2
}

# install shellcheck
edo wget https://storage.googleapis.com/shellcheck/shellcheck-latest.linux.x86_64.tar.xz
edo tar -xJf shellcheck-latest.linux.x86_64.tar.xz
edo mv shellcheck-latest/shellcheck "$HOME"/.local/bin/shellcheck

# check our script for errors
edo shellcheck ghcup