general: Investigate using square/protob

https://github.com/square/protob looks like it might be something worth investigating... Just figured I'd mention that here so we don't lose track of it.

@beriberikix

@beriberikix mentioned this when it was released. @rakyll said it was a mess for default values but otherwise was doing the right thing. I'm cool with keeping this open and potentially opening an issue to discuss our complaints. Would be nice to use a corporate-backed solution that can support us.

I don't think this protob has really taken off as a library and doesn't seem to be a very active or open project (no ci integration, no issues opened or closed, no PRs). I think the performance we get from Protobuf.js is good (and protob uses code from the library anyway). I don't think we will need to port our code to another protobuf library anytime soon and if we REALLY need to in the future, I have faith we will find the right solution in due time, so I'm closing this issue. Feel free to open if you think we might benefit from a better protobuf library or otherwise think we should continue to investigate it further.