* Remove gemfiles from version control to match same testing style as
Clearance and Suspenders.
* MiniTest does not need to be manually included as it is automatically
included by Rails by default.
* Add spring for Rails 4.1.
* Disable Spring to get specs to pass on Rails 4.1.
* Add therubyrhino for JRuby.
* Remove old references to Rails 3.
* Fix JRuby test where output is "1 runs", not "1 tests".
* Remove Rails 3.0 reference to "turn".
JRuby does not support setting/unsetting environment variables.
Thus, we will launch an entirely new process without the parents env when
we run `bundle install` inside the generated rails apps, forcing them to
use their own Gemfile, instead of the BUNDLE_GEMFILE setting from the main
gem codebase.
