Debian Changelog parser

This crate provides a parser for debian/changelog files, as described in the Debian policy, section 4.4.

The parser builds a CST. It is lossless - i.e. preserves formatting, and allows editing and partial parsing.

Example:

```rust

use std::io::Read;

fn main() -> Result<(), Box> { let file = std::fs::File::open("/usr/share/doc/rustc/changelog.Debian.gz")?; let mut gz = flate2::read::GzDecoder::new(file); let mut contents = String::new(); gz.readtostring(&mut contents)?; let changelog: debianchangelog::ChangeLog = contents.parse()?; for entry in changelog.entries() { println!( "{}: {}", entry.package().unwrap(), entry.version().unwrap().tostring() ); } Ok(()) } ```