Create a new non-modifiable buffer from a contiguous container.
template< typename T> const_buffer buffer( const T & data, typename constraint< is_contiguous_iterator< typename T::const_iterator >::value, defaulted_constraint >::type = defaulted_constraint());
A const_buffer
value equivalent to:
const_buffer( data.size() ? &data[0] : 0, data.size() * sizeof(typename T::value_type));