make a note about win32 C++ sym name demangling

git-svn-id: svn://localhost/ardour2/branches/3.0@6775 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/pbd/pbd/demangle.h

@@ -41,6 +41,11 @@ namespace PBD
 			return s;
 		}
 #endif
+
+                /* Note: on win32, you can use UnDecorateSymbolName.
+                   See http://msdn.microsoft.com/en-us/library/ms681400%28VS.85%29.aspx
+                */
+                
 		return typeid(obj).name();
 	}
 } // namespace