Introduce __cpp_lib_experimental_parallel_simd

Author: jaredhoberock

general.html

@@ -73,6 +73,14 @@ <h1>Feature-testing recommendations</h1>
           <td>201711</td>
           <td><code>&lt;experimental/algorithm&gt;</code></td>
         </tr>
+        <tr>
+          <td><ins>P0214R9</ins></td>
+          <td><ins>Data-Parallel Vector Types & Operations</ins></td>
+          <td><ins><cxx-ref to="parallel.simd"</cxx-ref></ins></td>
+          <td><ins><code>__cpp_lib_experimental_parallel_simd</code></ins>
+          <td><ins>????</td>
+          <td><ins><code>&lt;experimental/simd&gt;</code></ins></td>
+        </tr>
       </thead>
     </table>
   </cxx-section>