Includes Proto callable ``boost::proto::functional::rbegin``.

A PolymorphicFunctionObject type that invokes the `boost::rbegin()` accessor function on its arguments.

A PolymorphicFunctionObject type that invokes the `boost::rbegin()` accessor function on its arguments.

`proto::callable`
This(Range)
boost::range_reverse_iterator< typename boost::remove_reference<Range>::type >
typename boost::range_reverse_iterator< Range >::type `Range &`

`boost::rbegin(rng)`

typename boost::range_reverse_iterator< Range const >::type `Range const &`

`boost::rbegin(rng)`