Core compression and decompression implementation

[Daniel-Liu-c0deb0t]

The first step should be to compress and decompress a file using the gzip format. For maximum downstream flexibility, the zlib Rust bindings should be used directly instead of the flate2 library, which is too high level. The documentation for zlib can be found here. It is important to produce the correct headers, so that the compressed file can be recognized as a gzip file.

For testing, the compressed file produced by rust gzip should be able to be decompressed by rust gzip. Additionally, a c gzip file should be able to be decompressed by rust gzip, and a rust gzip compressed file should be able to be decompressed by c gzip.