Add `--prettyjson` flag to force pretty json formatting

Contributed by @echochamber in #106

Add --protofile support

This release adds support to compile an fdset on the fly using protoc, by specifying --protofile.
It also increases the max fetch per partition in Kafka (by @fegies in #99)

Add --protofile support

Pass in a .proto file directly to have pq compile it for you.

Performance improvements

Thanks to @fegies for 2 significant PRs. Details here:

• Performance improvement: #96
• Lower memory use: #97

Some extra fixes on my end, including:

• New Cargo clippy warnings taken into account
• Improvement to Python test scripts in utils/
• Replace docker with podman in the Makefile for the release process

General updates

Contribution from @vincentdephily:

• Fixes a security vulnerability
• Fixes building on systems with openssl >= 1.0
• Fixes a warning in recent rust versions

Add support for i32be streams (e.g. kafkacat output)

Thanks to @romand for this contribution - you can now pipe kafkacat to pq with the i32be stream option.

Rust 2018

Merge pull request #85 from sevagh/upkeep/edition-2018

Upkeep/edition 2018

Wait indefinitely for new kafka messages

Pq will now continually poll Kafka for new messages.

Performance improvements

@gnuvince added some additional performance improvements. Also most recently @shanipribadi contributed a first round of performance improvements which I didn't acknowledge, so I'll acknowledge it here.

Fix tty-checking logic

Fixes a bug with stdin/stdout tty checking.