Consumer

[taco-paco]

No description provided.

[Hyodar]

Some minor observations mainly. I'd like to take a look again after those are discussed, so marking it accordingly.

[Hyodar]

Okay, I ended up doing more changes than I initially expected, so I'll still leave the PR open for you to take a look tomorrow. Feel free to revert whatever, but I think mostly it's not something that will bring much of a discussion. Breaking down the most significant changes a bit so it's easier to consider:

• Removed some unnecessary TODOs - if you still think some of those are relevant, we can discuss it here. Let's try and keep it a bit cleaner, there were some that were already solved but the comment was still there.
• Moved the CLI to the cmd package, as in all the other submodules, and used urfave/cli, as in all other submodules.
• Refactored QueuesListener logic into Consumer - it was effectively implementable in a single function and it didn't seem like we were getting too much benefit from the QueuesListener abstraction. Plus, because of the rollup ID <-> channel name mapping, it was also strongly linked to Consumer through it since this is effectively a Consumer config.
• We consider each a rollup-related queue is simply "rollup" + str(id). This is simpler and I don't think we're losing anything with it.
• Added rollup IDs to ConsumerConfig. With the point above, this is equivalent to also knowing the queues.

There were also some minor changes, some related to my private comments on Slack.

[Hyodar]

Made some other small changes and integrated the consumer into the operator. I was originally going to do this in my PR after this was merged, but decided to do this instead. Same observations as above, feel free to do whatever.

[Hyodar]

LGTM