简单的获取和解压.tar.gz存档

简单的函数，旨在在Rust build.rs 脚本中使用，用于处理从HTTP获取以及使用预编译的二进制文件等解压.tar.gz存档的任务。

使用示例

use fetch_unroll::Fetch;

let pack_url = format!(
    concat!("{base}/{user}/{repo}/releases/download/",
            "{package}-{version}/{package}_{target}_{profile}.tar.gz"),
    base = "https://github.com",
    user = "katyo",
    repo = "aubio-rs",
    package = "libaubio",
    version = "0.5.0-alpha",
    target = "armv7-linux-androideabi",
    profile = "debug",
);

let dest_dir = "target/test_download";

// Fetching and unrolling archive
Fetch::from(pack_url)
    .unroll().strip_components(1).to(dest_dir)
    .unwrap();