New smart pointer documentation. Related clean-up of the smart pointer

library. Changing includes to include the new individual smart pointer
headers. Replacing old smart pointer library with an include of the new
smart pointer headers. Simplify ifdefs that involve the member templates
macros now that BOOST_MSVC6_MEMBER_TEMPLATES is also guaranteed to bet
set for platforms that have full member templates.


[SVN r12647]

shared_ptr_example2.hpp

@@ -1,6 +1,6 @@
 //  Boost shared_ptr_example2 header file  -----------------------------------//
 
-#include <boost/smart_ptr.hpp>
+#include <boost/shared_ptr.hpp>
 
 //  This example demonstrates the handle/body idiom (also called pimpl and
 //  several other names).  It separates the interface (in this header file)
@@ -16,7 +16,6 @@ class example
 {
  public:
   example();
-  ~example();
   example( const example & );
   example & operator=( const example & );
   void do_something();