DLPack integration for Rust

This crate contains a direct translation of the C header for DLPack, which is intended to be used inside Rust projects that want to offer a C API.

We also provide some tools to convert to and from Rust types, through the following cargo features:

• ndarray to convert from and to ndarray::Array
• pyo3 to convert from and to Python data, following the python specification for dlpack