`BOOST_HAS_VARIADIC_TMPL` and `BOOST_NO_CXX11_VARIADIC_TEMPLATES` can be
wrong, with Boost-1.57 and gcc>=5.0.
Fixes the following warnings with gcc>=5.0 in C++98 mode:
> CGAL-4.8-Ic-106/include/CGAL/array.h:78:31: warning: variadic templates only available with -std=c++11 or -std=gnu++11
> template< typename T, typename... Args >
> ^
> CGAL-4.8-Ic-106/include/CGAL/array.h:80:28: warning: variadic templates only available with -std=c++11 or -std=gnu++11
> cpp11::array< T, 1 + sizeof...(Args) >
> ^
> CGAL-4.8-Ic-106/include/CGAL/array.h:81:42: warning: variadic templates only available with -std=c++11 or -std=gnu++11
> make_array(const T & t, const Args & ... args)
> ^
Laurent Rineau
235b601b73