Installs rock for CI usage

rock-install.sh

#!/bin/bash

export ROCK_PATH="$HOME/.rock" # default
export PATH="$PATH:./.rock/bin:$ROCK_PATH/bin"

if [ -f "$ROCK_PATH/sources/rock" ]; then
  cd $ROCK_PATH/sources/rock
  git pull
else
  git clone --depth 1 https://github.com/vknabel/rock $ROCK_PATH/sources/rock
  cd $ROCK_PATH/sources/rock
fi

swift build
mkdir $ROCK_PATH/bin
cp $ROCK_PATH/sources/rock/.build/debug/rock $ROCK_PATH/bin

if [ -f "Rockfile" ]; then
  rock install
fi