Originally I had set up system testing to have one configuration option
to be set in the test environment. After thinking it over I think a
generated class on app creation would be best. The reason for this is
Capybara has a ton of configuration options that I'm sure some folks
want to use.

Thinking about how we handle screenshots, database transactions, and a
whole bunch of other settings it would be better for users to be able to
turn all of that on and off.

When an app or scaffold is generated a `test/system_test_helper.rb` test
helper will be generated as well. This will contain the class for tests
to inherit from `ActionSystemTestCase` which will inherit from
`ActionSystemTest::Base`. Here is where users can change the test
driver, remove the screenshot helper, and add their additional Capybara
configuration.