bumped default distro in demos, bound mariadb to all ips, added template explaination

faafo/faafo/api/templates/index.html

@@ -57,9 +57,9 @@ yb = {{ fractal.yb }}</pre>
 </div>
 {% endfor %}
 {{render_pagination(fractals)}}
-<!--
+<!-- requires POST request to have Content-Type: "application/vnd.api+json" header, would require Fetch API or XMLHTTPRequest etc.
 <div>
-  <form action="/v1/fractal" method="POST" enctype="application/vnd.api+json">
+  <form action="/v1/fractal" method="POST">
     <input type="submit" value="Create new fractals">
   </form>
 </div>