[selectors] Remove one :local-link issue that's clear in URL. Rephrase another one to be clearer.

Author: tabatkins

selectors/Overview.html

@@ -2804,18 +2804,13 @@ <h3 id=local-pseudo><span class=secno>8.3. </span> The local link
    belong to a hierarchical scheme, the functional pseudo-class matches
    nothing.
 
-  <p class=issue> Should a <code>:local-link(2)</code> match a link from the
-   document <code>http://example.com/foo</code> to itself? (This would make
-   Style 5 apply to Link 4.) (Relatedly, should a link from a document at an
-   opaque URL to itself also match?)
-
-  <p class=issue> If you're on a server architecture that allows both files
-   and folders of the same name at a given level, so that
-   "http://example.com/2011" and "http://example.com/2011/" are completely
-   different, it seems weird that (as currently specced), they'd both match
-   the document's url to 1 path level, even though they don't actually share
-   any path segments on your server. Should check with Anne and make sure we
-   match the URL spec.
+  <p class=issue> It's clear that, if the document URL has at least N
+   segments, then <code>:local-link(N)</code> only matches links whose URL
+   has at least N segments. (This lets you assign consistent semantics to
+   :local-link so that, for example, :local-link(2) means a "within-repo"
+   link on GitHub.) What about if the document url has less than N segments,
+   and the link is same-page? Should "null segments" count as matching, or
+   not?
 
   <h3 id=the-target-pseudo><span class=secno>8.4. </span> The target
    pseudo-class <a href="#target-pseudo"><code>:target</code></a></h3>

selectors/Overview.src.html

@@ -1883,17 +1883,13 @@ <h3 id="local-pseudo">
     the functional pseudo-class matches nothing.
 
   <p class="issue">
-    Should a <code>:local-link(2)</code> match a link from the document <code>http://example.com/foo</code>
-    to itself? (This would make Style 5 apply to Link 4.)
-    (Relatedly, should a link from a document at an opaque URL to itself also match?)
-
-  <p class='issue'>
-    If you're on a server architecture that allows both files and folders of the same name at a given level,
-    so that "http://example.com/2011" and "http://example.com/2011/" are completely different,
-    it seems weird that (as currently specced),
-    they'd both match the document's url to 1 path level,
-    even though they don't actually share any path segments on your server.
-    Should check with Anne and make sure we match the URL spec.
+    It's clear that, if the document URL has at least N segments, 
+    then <code>:local-link(N)</code> only matches links whose URL has at least N segments.
+    (This lets you assign consistent semantics to :local-link so that,
+    for example, :local-link(2) means a "within-repo" link on GitHub.)
+    What about if the document url has less than N segments,
+    and the link is same-page?
+    Should "null segments" count as matching, or not?
 
 
 <h3 id="the-target-pseudo">