install rails and run rails new

rails_new.sh

#!/bin/bash

if [ $# -ne 1 ]; then
  echo "引数1にrailsアプリ名を入れて下さい" 1>&2
  exit 1
fi

cat << EOS > Gemfile
source "http://rubygems.org"
gem "rails", "3.2"
EOS

bundle install --path vendor/bundle
mkdir $1
git init $1
bundle exec rails new $1 -T

rm -f Gemfile
rm -f Gemfile.lock
rm -rf .bundle
rm -rf vendor