update section role mapping

fixes #64

index.html

@@ -737,7 +737,7 @@ <h2 id="docconformance">Document conformance requirements for use of ARIA attrib
     </TR>
     <TR id="section" tabindex="-1">
       <TD><a href="https://www.w3.org/TR/html/sections.html#the-section-element"><code>section</code></a>
-      <TD><code>role=<a href="#index-aria-region">region</a></code></TD>
+      <TD><code>role=<a href="#index-aria-region">region</a></code> if the <a href="https://www.w3.org/TR/html/sections.html#the-section-element">section</a> element has an <a href="https://w3c.github.io/html-aam/#dfn-accessible-name" data-link-type="dfn">accessible name</a>. Otherwise, <a>no corresponding role</a>.</TD>
       <TD><p>Role: <code><a href="#index-aria-alert">alert</a>, <a href="#index-aria-alerTDialog">alertdialog</a>, <a href="#index-aria-application">application</a>, <a href="#index-aria-banner">banner</a>, <a href="#index-aria-complementary">complementary</a>, <a href="#index-aria-contentinfo">contentinfo</a>, <a href="#index-aria-dialog">dialog</a>, <a href="#index-aria-document">document</a>,<a href="#index-aria-feed">feed</a></code> - <span class="new-feature">(new)</span>, <code><a href="#index-aria-log">log</a>, <a href="#index-aria-main">main</a>, <a href="#index-aria-marquee">marquee</a>, <a href="#index-aria-navigation">navigation</a>, <a href="#index-aria-search">search</a>, <a href="#index-aria-status">status</a></code> or <code><a href="#index-aria-tabpanel">tabpanel</a></code>  - <span class="changed-feature">(changed)</span></p>
         <p><a href="#index-aria-global">global <code>aria-*</code> attributes</a> and any <code>aria-*</code> attributes applicable to the
           allowed roles</p></TD>