title: Retrieve matched text from input.text.matches and store into context variable in watson conversation
body: <p>I am dealing with <strong>IBM Watson Conversation</strong>. I have a text that contains few <strong>letters and digits</strong> i.e. <code>age is 26</code>.  </p>
  
  <p>I have written a regex to match the digits from the text. It is done using <code>.*?[0-9]+.*?</code>. Now, I want those matched digits into <strong>context variables</strong>. </p>
  
  <p><em>How to place the matched digits into context variable ?</em></p>
  
  <p>When my condition matches with having <code>input.text.matches('.*?[0-9]+.*?')</code>, then I want to place only digits to my <strong>context variable</strong>. </p>
  
  <p><strong>For Ex:</strong></p>
  
  <pre><code>{
      "context": {
                 "digit": { input.text } 
      }
  }
  </code></pre>
  
  <p>Here <code>input.text</code> takes the whole text and places it into <strong>digit</strong> variable. </p>
  
  <p><strong>How to place only digits by applying regular expression on text ?</strong></p>