title: Interacting with an element through xpath selector
body: <p>I see a lot of documentation and examples of people using xpath with capybara but for some reason I don't find anything on how to do the simplest thing... click a (button|link|whatever) identified by an xpath selector. How does one accomplish a step definition like:</p>
  
  <pre><code>Given /^I click the element identified by xpath "([^"]*)"$/ do |xpath_selector|
    click_button(xpath_selector)
  end
  </code></pre>