Support SASL/PLAIN and SASL/SCRAM mechanisms

[dylanmei]

Description of the changes

Add support for additional SASL mechanisms for authenticating with Kafka brokers.

• SASL/PLAIN: https://kafka.apache.org/documentation/#security_sasl_plain
• SASL/SCRAM: https://kafka.apache.org/documentation/#security_sasl_scram

Link the issue it solves: #58

PR Review Checklist

Author

• the PR should focus on a single subject. Change only relevant files to the problem you’re working on
  Clean and format the code
• add unit tests for your changes and make sure all unit tests are passing
• add a risk label after carefully considering the "blast radius" of your changes
• describe the intent of your changes in the description. don't just rewrite your code in prose
• assign at least one reviewer
• address the feedback

Reviewer

• review code for readability
• verify that high risk behavior changes are well tested
• check license for any new external dependency
• ask questions about anything that isn't clear and obvious
• approve the PR when you consider it's good to merge

[CLAassistant]

All committers have signed the CLA.

[camdencheek]

Hi @dylanmei -- thanks for the PR! That was a quick turnaround. At a brief scan, this looks great. I'll do my best to provide a proper review ASAP, and get this merged in.

[camdencheek]

Hi @dylanmei -- so sorry for the slow turnaround on this. It's been a whirlwind of a week. I looked over the PR and it just needed a tiny bit of touchup (mostly linter complaints), but I included my local changes in the merge. These changes will be released as part of v2.13.0, which I'm kicking off a release for right now

[tmancill]

@camdencheek Any update on this?

[camdencheek]

@tmancill this was released yesterday. It's available as part of v2.13.0. I'll try to get documentation updated on it soon

[Neustradamus]

@dylanmei: Thanks a lot for all about SCRAM.

Linked to:

• State of Play scram-sasl/info#1