Unofficial bindings for the [catboost] library.

This crate is meant as a new and better replacement
of the rust package that is provided in the [catboost]
repository at `catboost/rust-package` because that one
is really outdated and doesn't work.

The main difference is, that this library will not build
catboost from source, and instead bundle the distributed
binaries and link them dynamically into the resulting binary.

[catboost]: https://github.com/catboost/catboost