Add third-party ESP-IDF library.

Author: mrstegeman

framework/index.html

@@ -919,6 +919,12 @@ <h2>Third-Party Libraries</h2>
                 Go (by dravenk)
               </a>
             </div>
+            <div class="library">
+              <a href="https://github.com/akshayvernekar/esp-webthing">
+                <img alt="GitHub logo" src="images/github.png" />
+                ESP-IDF (by akshayvernekar)
+              </a>
+            </div>
           </section>
         </div>
       </section>