add netlify logo as per their OSS license requirements (#1511)

* add netlify logo as per their OSS license requirements

* Update footer-en.html

Add Netlify logo to footer as discussed

* Update home.html

Moved Netlify logo to footer per discussion

* wrap in div to space the logo

---------

Co-authored-by: Rand McKinney <crandmck@yahoo.com>

_includes/footer/footer-en.html

@@ -7,17 +7,22 @@
   <br>
   Community translation available for: <a href="/sk/">Slovak</a>, <a href="/uk/">Ukrainian</a>, <a href="/uz/">Uzbek</a>, <a href="/tr/">Turkish</a> and <a href="/th/">Thai</a>.
   </section>
-  <div id="footer-content">
+    <div id="footer-content">
+      <div>
+        <a href="https://www.netlify.com">
+          <img src="https://www.netlify.com/v3/img/components/netlify-color-accent.svg" alt="Preview Deploys by Netlify" style="width: 50px;" />
+        </a>
+      </div>
       <div id="github">
         <a class="github-button" href="https://github.com/expressjs/expressjs.com" data-icon="octicon-star" aria-label="Star expressjs/expressjs.com on GitHub">Star</a>
       </div>
       <div id="sponsor"><a href="https://expressjs.com">Express</a> is a project of the <a href="https://openjsf.org">OpenJS Foundation</a>.</div>
       <div id="fork"><a href="https://github.com/expressjs/expressjs.com">Fork the website on GitHub</a>.</div>
       <div>Copyright &copy; 2017 StrongLoop, IBM, and other expressjs.com contributors.</div>
-  </div>
-  <div id="license">
+    </div>
+    <div id="license">
       <a rel="license" href="http://creativecommons.org/licenses/by-sa/3.0/us/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by-sa/3.0/us/80x15.png" /></a> This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by-sa/3.0/us/">Creative Commons Attribution-ShareAlike 3.0 United States License</a>.
-  </div>
+    </div>
 </footer>
 
 <script async defer src="https://buttons.github.io/buttons.js"></script>