Vendor dependencies

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vendor/adler/README.md

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+# Adler-32 checksums for Rust
+
+[![crates.io](https://img.shields.io/crates/v/adler.svg)](https://crates.io/crates/adler)
+[![docs.rs](https://docs.rs/adler/badge.svg)](https://docs.rs/adler/)
+![CI](https://github.com/jonas-schievink/adler/workflows/CI/badge.svg)
+
+This crate provides a simple implementation of the Adler-32 checksum, used in
+the zlib compression format.
+
+Please refer to the [changelog](CHANGELOG.md) to see what changed in the last
+releases.
+
+## Features
+
+- Permissively licensed (0BSD) clean-room implementation.
+- Zero dependencies.
+- Zero `unsafe`.
+- Decent performance (3-4 GB/s).
+- Supports `#![no_std]` (with `default-features = false`).
+
+## Usage
+
+Add an entry to your `Cargo.toml`:
+
+```toml
+[dependencies]
+adler = "1.0.2"
+```
+
+Check the [API Documentation](https://docs.rs/adler/) for how to use the
+crate's functionality.
+
+## Rust version support
+
+Currently, this crate supports all Rust versions starting at Rust 1.31.0.
+
+Bumping the Minimum Supported Rust Version (MSRV) is *not* considered a breaking
+change, but will not be done without good reasons. The latest 3 stable Rust
+versions will always be supported no matter what.