Add sign up for updates link to homepage banner

tool/template-home.html

@@ -22,6 +22,7 @@
       <div class="blurb col-sm-12">
         <p>The <a href="#xrp_ledger_intro">XRP Ledger</a> is built on <code>rippled</code>, an open-source technology that anyone can use.</p>
         <p>Use the tools and information provided here to integrate with and contribute to the open-source platform.</p>
+        <p>Want more? Get updates about XRP Ledger webinars, releases, and documentation! <a class="btn btn-light ml-3" href="https://goo.gl/forms/sHMFxU8dKiTUaltE3">Sign up! <i class="fa fa-external-link" aria-hidden="true"></i></a></p>
       </div>
     </div>
   </section>