Merge pull request #3428 from vespa-engine/kkraune/slice

add sliceId example

en/reference/document-v1-api-reference.html

@@ -455,10 +455,11 @@ <h2 id="request-parameters">Request parameters</h2>
   <td>
     <p id="sliceid">
       The slice number of the visit represented by this HTTP request. This number must be non-negative
-      and less than the number of <a href="#slices">slices</a> specified for the visit.
+      and less than the number of <a href="#slices">slices</a> specified for the visit -
+      e.g., if the number of slices is 10, <code>sliceId</code> is in the range [0-9].
       {% include note.html content="If the number of distribution bits change during a sliced visit,
       the results are undefined.
-      Thankfully, this is a very rare occurrence, and is only triggered when adding content nodes." %}
+      Thankfully, this is a very rare occurrence and is only triggered when adding content nodes." %}
     </p>
   </td>
 </tr><tr>