Protobuf 3

[jrconlin]

So... Yeah.

Protobuf-3.

This compiles with Protobuf-3 but holy cow are there breaking changes. (So many breaking changes.)
Granted, the changes are good, and they do make things a lot more Rust-y, but wow, just so, so many breaking changes.

e.g. You now no longer need to create a mutable version of some structure like PubsubMessage and then call getter/setter functions. You can instead use

PubsubMessage{
    data: message.to_owned().into_bytes(),
    publish_time: protobuf::MessageField(
        Some(Box::new(
            protobuf::well_know_types::timestamp::Timestamp{
                seconds: some_timestamp
            }))
       ),
   ..Default::default()
}

Neat, huh? Yep. (So many breaking changes.)

You can also replace instances of RepeatingField() with vec![]

(quietly sobs about how many changes that's going to require.)