Adding documentation for make_shared and allocate_shared to smart_ptr docs.

It is adopted from n2351 "Improving shared_ptr for C++0x, Revision 2". 
Also includes some minor corrections.
Refs #1897



[SVN r51699]

libs/libraries.htm

@@ -246,7 +246,7 @@ how to download, build, and install the libraries.</p>
          slots callback implementation, from Doug Gregor.</li>
     <li><a href="signals2/index.html">signals2</a> - managed signals &amp;
          slots callback implementation (thread-safe version 2), from Frank Mori Hess.</li>
-    <li><a href="smart_ptr/index.html">smart_ptr</a> - Five smart
+    <li><a href="smart_ptr/index.html">smart_ptr</a> - Six smart
         pointer class templates, from Greg Colvin, Beman Dawes,
         Peter Dimov, and Darin Adler.</li>
     <li><a href="statechart/doc/index.html">statechart</a> - Arbitrarily

libs/smart_ptr

@@ -1 +1 @@
-Subproject commit dc3ffc5f4b3cc82ab6cf0a6ea2dae5ab3d249c9f
+Subproject commit fbc6919eae7bbdc0a4b8924ebcc582c6df782102