docs/templates: Add unix and zephyr quickref links to top-index.

Signed-off-by: Damien George <damien@micropython.org>

docs/templates/topindex.html

@@ -66,6 +66,14 @@
         <a class="biglink" href="{{ pathto("wipy/quickref") }}">Quick reference for the WiPy/CC3200</a><br/>
         <span class="linkdescr">pinout for the WiPy/CC3200, snippets of useful code, and a tutorial</span>
       </p>
+      <p class="biglink">
+        <a class="biglink" href="{{ pathto("unix/quickref") }}">Quick reference for UNIX and Windows</a><br/>
+        <span class="linkdescr">command-line reference</span>
+      </p>
+      <p class="biglink">
+        <a class="biglink" href="{{ pathto("zephyr/quickref") }}">Quick reference for the Zephyr port</a><br/>
+        <span class="linkdescr">snippets of useful code and a tutorial</span>
+      </p>
     </td>
   </tr></table>