Add explanatory comment to check script

check.sh

@@ -0,0 +1,46 @@
+#!/usr/bin/env bash
+
+# This script is used by Makers to ensure that the challenges stay up to date.
+# If you're a student, you don't need to run it. But you can if you like!
+
+set -Eeuo pipefail
+trap cleanup SIGINT SIGTERM ERR
+
+script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &>/dev/null && pwd -P)
+
+setup_colors() {
+  if [[ -t 2 ]] && [[ -z "${NO_COLOR-}" ]] && [[ "${TERM-}" != "dumb" ]]; then
+    NOFORMAT='\033[0m' RED='\033[0;31m' GREEN='\033[0;32m' ORANGE='\033[0;33m' BLUE='\033[0;34m' PURPLE='\033[0;35m' CYAN='\033[0;36m' YELLOW='\033[1;33m'
+  else
+    NOFORMAT='' RED='' GREEN='' ORANGE='' BLUE='' PURPLE='' CYAN='' YELLOW=''
+  fi
+}
+
+cleanup() {
+  trap - SIGINT SIGTERM ERR
+  die "${RED}Checks failed${NOFORMAT}"
+}
+
+msg() {
+  echo >&2 -e "${1-}"
+}
+
+die() {
+  local msg=$1
+  local code=${2-1} # default exit status 1
+  msg "$msg"
+  exit "$code"
+}
+
+setup_colors
+
+msg "${BLUE}Integrity check using Ruby version ${ORANGE}$(ruby -v)${NOFORMAT}"
+msg "${BLUE} • Installing bundler${NOFORMAT}"
+gem install bundler
+msg "${BLUE} • Running bundle install${NOFORMAT}"
+bundle install
+msg "${BLUE} • Running rspec${NOFORMAT}"
+bundle exec rspec
+msg "${BLUE} • Running rubocop${NOFORMAT}"
+bundle exec rubocop
+exit 0