Add Google Tag Manager snippet

Author: fdabrandao

_templates/ampl-pages.html

@@ -1,3 +1,15 @@
+<!-- Google Tag Manager -->
+<script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
+new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
+j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
+'https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
+})(window,document,'script','dataLayer','GTM-WDR59JC');</script>
+<!-- End Google Tag Manager -->
+<!-- Google Tag Manager (noscript) -->
+<noscript><iframe src="https://www.googletagmanager.com/ns.html?id=GTM-WDR59JC"
+height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
+<!-- End Google Tag Manager (noscript) -->
+
 <div class="dropdown-header">AMPL Resources</div>
 <li><a class="btn btn-sm dropdown-item" target="_blank" href="https://ampl.com/"><i class="fas fa-home fa-fw fa-lg"></i> AMPL.com</a></li>
 <li><a class="btn btn-sm dropdown-item" target="_blank" href="https://discuss.ampl.com/"><i class="fab fa-discourse fa-fw fa-lg"></i>AMPL Support Forum</a></li>