Upgrade example Rails provider/consumer app to Rails 3

Upgrade the example Rails provider/consumer app to work on Rails 3:

* Run rake rails:upgrade
* Run rails new .
* Remove script/* files (except for script/rails)
* Rename templates
* Update routes for Rails 3
* Install CSRF token in provider form
* Exclude action and controller options from parameters when verifying
  return_to url
* Cleanup a few unneeded files like .gitignore for unused directories
  and application layout that were generated for Rails 3