title: Print the current (wrong) data in an Ajv error message
body: <p>I wish to make Ajv print the piece of my data that is wrong when an error is detected.</p>
  <p>I'll make a couple of examples of how Ajv currently behaves and how I wish for it to act:</p>
  <hr />
  <h5>Example 1</h5>
  <ul>
  <li>schema: <code>{const:&quot;hello!&quot;}</code></li>
  <li>data: <code>&quot;hi&quot;</code></li>
  <li>error reported by Ajv: <code>data must be equal to constant</code></li>
  <li>error I wish to see: <code>data (&quot;hi&quot;) must be equal to constant (&quot;hello!&quot;)</code></li>
  </ul>
  <h5>Example 2</h5>
  <ul>
  <li>schema: <code>{type:&quot;object&quot;, properties:{&quot;x&quot;:{}}, additionalProperties:false}</code></li>
  <li>data: <code>{x:1, y:2}</code></li>
  <li>error reported by Ajv: <code>data must NOT have additional properties</code></li>
  <li>error I wish to see: <code>data must NOT have additional properties (found &quot;y&quot;)</code></li>
  </ul>
  <hr />
  <p>And so on and so forth. I want more information to help me debug my data for any kind of error, anywhere in the data.</p>
  <p>I found lots of information pointing to the ajv-errors package but couldn't figure out how to use it to achieve what I want.</p>
  <p>Could anyone suggest if it's possible to achieve what I want and how?</p>