asw-v01: archive deferred content (packs, site, lab, legacy examples)

- 2.1: packs/ -> archive/packs/
- 2.2: site/ -> archive/site/
- 2.3: src/lab/ -> archive/lab/
- 2.4: examples/ -> archive/examples-legacy/ (SSI-based)

site/layouts/page/single.html

@@ -1,11 +0,0 @@
-{{ define "content" }}
-  <article>
-    <header>
-      <h1>{{ .Title }}</h1>
-      {{- with .Description }}
-      <p>{{ . }}</p>
-      {{- end }}
-    </header>
-    {{ .Content }}
-  </article>
-{{ end }}