[boost] [fusion] Support for classic boost::tuple

Hi, Ok, as promised. Support for classic boost::tuple has been added. Now yer ole boost tuples are full fusion citizens. Now boost::tuple can do for_each, transform, fold, find, assign/convert to other fusion sequences, etc. Now there are 3 adapted sequences: 1) std::pair 2) boost::array 3) boost::tuples::tuple And, from the start, of course all MPL sequences are full fusion citizens too. I hope more boost libraries can be "fusion-ified" :) Have fun!!! Regards, -- Joel de Guzman http://www.boost-consulting.com http://spirit.sf.net