Update capybara

Looks like the recent gem updates took out capybara.  This fixes the
following error

`raise_too_low_error': You are using capybara 2.1.0. RSpec requires version >= 2.2.0. (RSpec::Support::LibraryVersionTooLowError)`
Merge pull request #346 from ophrescue/update-capybara-version

Update capybara