Added adapter for std::tuple (only for implementations using variadic templates)

[SVN r74546]

include/boost/fusion/iterator/advance.hpp

@@ -1,7 +1,7 @@
 /*=============================================================================
     Copyright (c) 2001-2011 Joel de Guzman
 
-    Distributed under the Boost Software License, Version 1.0. (See accompanying 
+    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)
 ==============================================================================*/
 #if !defined(FUSION_ADVANCE_09172005_1146)
@@ -18,7 +18,7 @@
 namespace boost { namespace fusion
 {
     struct random_access_traversal_tag;
-        
+
     // Special tags:
     struct iterator_facade_tag; // iterator facade tag
     struct boost_array_iterator_tag; // boost::array iterator tag
@@ -59,7 +59,7 @@ namespace boost { namespace fusion
         template <>
         struct advance_impl<std_pair_iterator_tag>;
     }
-    
+
     namespace result_of
     {
         template <typename Iterator, int N>