title: How to select nodes by matching text
body: <p>If I have a bunch of elements like: </p>
  
  <pre><code>&lt;p&gt;A paragraph &lt;ul&gt;&lt;li&gt;Item 1&lt;/li&gt;&lt;li&gt;Apple&lt;/li&gt;&lt;li&gt;Orange&lt;/li&gt;&lt;/ul&gt;&lt;/p&gt;
  </code></pre>
  
  <p>Is there a built-in method in Nokogiri that would get me all <code>p</code> elements that contain the text "Apple"? (The example element above would match, for instance).</p>