Convert to c++ extension?

[RussWolfinger]

Hi @yeezhu, Thanks very much for the nice research and implementation. Looks like pytorch has deprecated support for c extensions: https://gitlab.com/elynn/pytorch/commit/15d28e400f71c50848b760ca188ebc885ee433d8 . Would like to request conversion to c++ so this will run with pytorch 0.4.1. Much obliged.