Rails 4 prints help for "rails new" when running "rails console"

Upgrading an existing Rails 3 app to Rails 4 results in a `rails` command that only ever prints the help for `rails new`. Here are reproduction steps:

```
mkdir app
cd app
curl -sLo Gemfile http://git.io/G3awjw
bundle install --binstubs --path vendor/bundle
bundle exec rails new .
bundle exec rails runner "puts 'WORKING'" #=> WORKING
sed -i -e 's/3.2.13/4.0.0.beta1/g' Gemfile # update to rails 4
ruby -i -ne 'print if not /coffee|sass/' Gemfile
bundle update rails
rm -rf script/rails # like you're supposed to
bundle exec rails runner "puts 'WORKING'" #=> help for rails new
```

There are angry developers about this issue available for perusal in carlhuda/bundler#2253.