Add modal API
Merge branch 'notification_api' of https://github.com/mikepack/capybara into modal

* 'notification_api' of https://github.com/mikepack/capybara:
  Add modal API
Fix save_and_open_screenshot for 3rd drivers

The screenshot path will not start with `capybara/` for 3rd drivers like
poltergeist since they aren't on capybara itself.

See https://travis-ci.org/teampoltergeist/poltergeist/jobs/28737963#L534
Add adjustable wait time and text matching for modals
remove unnecessary respond_to_prompt, change parameter name from :response to :with to match fill_in, take text/regex to match as optional inline parameter instead of option
Merge pull request #1347 from sobrinho/master

Fix save_and_open_screenshot for 3rd drivers
Fix typo in test description
document expected behavior of Driver#accept_modal and #dismiss_modal
Merge pull request #1322 from jnicklas/modal

API for operation with modal dialogs
fix Base#dismiss_modal definition