Adjust developer docs front page and add JSON links on HTTP page

apidocs/http/index.html

@@ -64,6 +64,10 @@
       <code>http://microscope.local:5000/docs</code>
     </p>
 
+    <p>
+      You can also directly inspect the OpenAPI JSON file <a href="./openapi.json">openapi.json</a> or the WC3 "Web of Things" Thing Descriptions JSON <a href="./thing_descriptions.json">thing_descriptions.json</a>
+    </p>
+
     <aside>
       Replace <strong>microscope.local</strong> with your microscope's hostname or IP address
       if your network uses a different name.