Specify process for naming future architectures

Author: timthelion

serialization.md

@@ -181,7 +181,7 @@ Here is an example image JSON file:
             <li>linux</li>
         </ul>
         More values may be supported in the future and any of these may or may
-        not be supported by a given container runtime implementation.
+        not be supported by a given container runtime implementation. Future values will be consistent with those already canonicalized by the <a href="https://www.debian.org/ports/">Debian ports list</a>.
     </dd>
     <dt>
         checksum <code>string</code>