get_error_info returns raw pointer instead of shared_ptr (breaking change)

diagnostic_information can now be called with boost::exception or std::exception object.
BOOST_THROW_EXCEPTION can now be used even if exceptions are disabled.
added functions: current_exception_diagnostic_information, current_exception_cast
documentation updated to match.

[SVN r52225]

include/boost/exception/current_exception_cast.hpp

@@ -0,0 +1,34 @@
+//Copyright (c) 2006-2008 Emil Dotchevski and Reverge Studios, Inc.
+
+//Distributed under the Boost Software License, Version 1.0. (See accompanying
+//file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef UUID_7E83C166200811DE885E826156D89593
+#define UUID_7E83C166200811DE885E826156D89593
+
+namespace
+boost
+    {
+    template <class E>
+    inline
+    E *
+    current_exception_cast()
+        {
+        try
+            {
+            throw;
+            }
+        catch(
+        E & e )
+            {
+            return &e;
+            }
+        catch(
+        ...)
+            {
+            return 0;
+            }
+        }
+    }
+
+#endif