* Added code to find drivers that are externally loaded
* Support wait_until in driver
* Optionally make xpath absolute paths absolute
* Add predicate to test if drivers shortcircuit waits and tweak spec
* Allows file:/// (envjs) urls as well as http://foo urls (rack)
* Warm the driver in wait_until tests so the init cost isn't included in the test
Capybara::WaitUntil
- should return result of yield if it returns true value within timeout
- should keep trying within timeout
- should raise Capybara::TimeoutError if block fails to return true within timeout