Update all versions of outdated specs with warning

[gkellogg]

The various specs which went on to be recommendations, or were otherwise obsoleted, should have headers similar to that used by W3C for old spec versions (e.g., https://www.w3.org/TR/2020/PR-json-ld11-framing-20200507/).

<p class="outdated-warning" tabindex="-1" role="dialog" aria-modal="true" aria-labelledby="outdatedWarning">
  <strong id="outdatedWarning">This version is outdated!</strong>
  <span>For the latest version, please look at
    <a href="https://www.w3.org/TR/json-ld11-framing/">https://www.w3.org/TR/json-ld11-framing/.</a>
  </span>
  <button>▾ collapse</button>
</p>

It might just need to include <script src="https://www.w3.org/scripts/TR/2016/fixup.js"></script> at the end, but not sure of the mechanics.

[gkellogg]

(Actually, I see it already has a header that effectively does that).

[gkellogg]

Never mind, already done!