frontends" added reference to Dynamic Web TWAIN

Thanks to @xulihang for the tip.

sane-frontends.html

@@ -206,6 +206,10 @@
       <li>
 	<a href="https://github.com/sbs20/scanservjs">scanservjs</a> an updated version of scanserv based on nodejs.
       </li>
+	  <li>
+	<a href="https://www.dynamsoft.com/web-twain/overview/">Dynamic Web TWAIN</a> is a document scanning SDK based on SANE, TWAIN and ICA, etc.
+      </li>
+
 <!--  Link dead?
       <li>
 	<a href="http://psf.absolut-confus.de/" target="_top">PSF</a> (PHP Sane