Update text-emphasis to exclude word separator characters and mark punctuation as an issue

Author: fantasai

css3-text/Overview.src.html

@@ -3096,13 +3096,17 @@ <h4 id="text-emphasis-style"><span class="secno">8.2.1</span>
     <p>The marks are drawn once for each grapheme cluster. However,
       emphasis marks are not drawn for a grapheme cluster consisting of:</p>
     <ul>
-      <li>Characters for which ruby is drawn in the same position.</li>
-      <li>Characters belonging to the Unicode separator classes (Z*).
+      <li>Characters for which ruby is drawn in the same position as
+        the emphasis mark.</li>
+      <li><a href="#word-separator">Word separators</a> or characters
+        belonging to the Unicode separator classes (Z*).
         (But note that emphasis marks <em>are</em> drawn for a space
          that combines with any combining characters.)</li>
       <li>Characters belonging to the Unicode classes for control codes
         and unassigned characters (Cc, Cf, Cn).</li>
-      <li><span class="issue">Anything else?</span></li>
+      <li><span class="issue">Anything else? Probably need to exclude
+        punctuation, but which punctuation exactly? Can we determine
+        that Unicode-wide?</span></li>
     </ul>
 
     <h4 id="text-emphasis-color"><span class="secno">8.2.2</span>