[wwwdocs] Document more libstdc++ changes

[Jonathan Wakely]

Committed to wwwdocs git.



commit 578a32e2f9215ccf96bd580d275fa12c22aa45a5
Author: Jonathan Wakely <jwak...@redhat.com>
Date:   Fri Feb 21 10:27:39 2020 +0000

    Document more libstdc++ changes

diff --git a/htdocs/gcc-10/changes.html b/htdocs/gcc-10/changes.html
index 5a959a10..2920714a 100644
--- a/htdocs/gcc-10/changes.html
+++ b/htdocs/gcc-10/changes.html
@@ -348,13 +348,22 @@ a work-in-progress.</p>
       </li>
       <li> <code>std::ssize</code>, <code>std::to_array</code>. </li>
       <li>
-        <code>&lt;concepts&gt;</code> and some parts of
-        <code>&lt;ranges&gt;</code>.
+        Library concepts in <code>&lt;concepts&gt;</code> and
+        <code>&lt;iterator&gt;</code>.
       </li>
-      <li> <code>&lt;compare&gt;</code>. </li>
-      <li> <code>&lt;numbers&gt;</code>. </li>
+      <li>
+        Constrained algorithms in <code>&lt;ranges&gt;</code> and
+        <code>&lt;memory&gt;</code> (thanks to Patrick Palka).
+      </li>
+      <li> Three-way comparisons in <code>&lt;compare&gt;</code>. </li>
+      <li>
+        <code>std::construct_at</code>, <code>std::destroy</code>,
+        constexpr <code>std::allocator</code>.
+      </li>
+      <li> Mathematical constants in <code>&lt;numbers&gt;</code>. </li>
     </ul>
   </li>
+  <li>Support for RDSEED in <code>std::random_device</code>.</li>
   <li>
     Reduced header dependencies, leading to faster compilation for some code.
   </li>