Add tests and flat includes.

- 24e95c3 Add tests for [#9914](https://svn.boost.org/trac/boost/ticket/9914)
 - I'm not sure [#9914](https://svn.boost.org/trac/boost/ticket/9914) is already fixed or not though the results of Boost.Regression will help us.
- b7febc8 Flat includes for std::tuple
 - As commit message. 

I believe there is no pain to merge.