Include capybara dsl in request specs

Capybara, after 2.0 is set to use 'feature specs' instead of 'request specs' so this is needed to have the DSL.

See: http://www.andylindeman.com/2012/11/11/rspec-rails-and-capybara-2.0-what-you-need-to-know.html

Spec results before this change:

`234 examples, 30 failures`

After:

`234 examples, 14 failures`


Include it in your PR if you agree :smiley: