Rails bin/dev with overmind/hivemind support

dev.sh

#!/usr/bin/env sh

# Default to port 3000 if not specified
export PORT="${PORT:-3000}"

if overmind -v &> /dev/null; then
  overmind start -f Procfile.dev
  exit
fi

if hivemind -v &> /dev/null; then
  hivemind Procfile.dev
  exit
fi

if ! gem list foreman -i --silent; then
  echo "Installing foreman..."
  gem install foreman
fi

exec foreman start -f Procfile.dev "$@"