[] (0) Make rel=next/prev be non-hierarchical, just sequenced.

git-svn-id: http://svn.whatwg.org/webapps@1126 340c8d12-0b0e-0410-8428-c7bf67bfef74

index

    <a href="#hyperlink1" title="hyperlink link">hyperlink</a>.
 
   <p>The <code title=rel-next><a href="#next">next</a></code> keyword
-   indicates that the document is part of a hierarchical structure, and that
-   the link is leading to the document that is the next sibling of the
-   current document.
+   indicates that the document is part of a sequence, and that the link is
+   leading to the document that is the next logical document in the sequence.
 
   <h6 id=link-type21><span class=secno>4.12.3.19.5. </span>Link type "<dfn
    id=prev title=rel-prev><code>prev</code></dfn>"</h6>
    <a href="#hyperlink1" title="hyperlink link">hyperlink</a>.
 
   <p>The <code title=rel-prev><a href="#prev">prev</a></code> keyword
-   indicates that the document is part of a hierarchical structure, and that
-   the link is leading to the document that is the previous sibling of the
-   current document.
+   indicates that the document is part of a sequence, and that the link is
+   leading to the document that is the previous logical document in the
+   sequence.
 
   <p><strong>Synonyms</strong>: For historical reasons, user agents must also
    treat the keyword "<code title="">previous</code>" like the <code

source

   title="hyperlink link">hyperlink</span>.</p>
 
   <p>The <code title="rel-next">next</code> keyword indicates that the
-  document is part of a hierarchical structure, and that the link is
-  leading to the document that is the next sibling of the current
-  document.</p>
+  document is part of a sequence, and that the link is leading to the
+  document that is the next logical document in the sequence.</p>
 
 
   <h6>Link type "<dfn title="rel-prev"><code>prev</code></dfn>"</h6>
   title="hyperlink link">hyperlink</span>.</p>
 
   <p>The <code title="rel-prev">prev</code> keyword indicates that the
-  document is part of a hierarchical structure, and that the link is
-  leading to the document that is the previous sibling of the current
-  document.</p>
+  document is part of a sequence, and that the link is leading to the
+  document that is the previous logical document in the sequence.</p>
 
   <p><strong>Synonyms</strong>: For historical reasons, user agents
   must also treat the keyword "<code title="">previous</code>" like