pe: add authenticode support

[baloo]

Authenticode is the hashing format used to sign PE binaries. This provides the hash to be signed.

Usage:

use goblin::pe::PE;
use sha2::Sha256;
use std::{fs::File, io::Read};

fn main() {
    let mut buf = Vec::new();
    let mut f =
        File::open("/nix/store/bhsxra1hc7yhja2kzw5rdds90i3w3a54-linux-5.10.147/bzImage").unwrap();
    f.read_to_end(&mut buf).unwrap();

    let pe = PE::parse(&buf).unwrap();
    let hash = pe.authenticode_digest::<Sha256>();

    println!("hash: {:x?}", hash);
}

Fixes #355 cc @RaitoBezarius

[m4b]

For similar reasons I've noted in https://github.com/m4b/goblin/pull/360 it's going to take some serious convincing to add more deps to goblin.

[baloo]

I get the point about not adding dependencies to goblin itself. I'd be more than happy to implement those as trait and get that implemented in a dependency of both goblin and digest, but there are some data that I need goblin to emit. Namely, the sections I need to omit from the authenticode computation, I don't think I can't get that done outside goblin.

I think it would also be nice to have the "source bytes" in the PE objects, if you're alright with that.

Anyway, thanks for maintaining goblin in the first place.

[baloo]

(made an alternative in #362)