message: add missing headers to action/slice.hpp, fixes
diff: #include <functional>
  #include <meta/meta.hpp>
  #include <range/v3/range_fwd.hpp>
  +#include <range/v3/distance.hpp>
  +#include <range/v3/view_interface.hpp>
  #include <range/v3/action/action.hpp>
  #include <range/v3/action/erase.hpp>
  #include <range/v3/utility/functional.hpp>
  