Make rabbitmq_queue gathering be configurable

[ildarsv]

Required for all PRs:

• Signed CLA.
• Associated README.md updated.
• Has appropriate unit tests.

PR for the #3701

[danielnelson]

I'm somewhat adverse to adding new boolean options, as they don't scale up very well and become confusing especially if they become dependent on other options. What I'd like to do is something similar to our other filter options and have an include and exclude list that supports globs:

queues_exclude = ["*"]

There is a good example of this in the docker input with container_name_include and container_name_exclude.

[ildarsv]

@danielnelson
Yes, It is not the best solution, but in case you have 1000+ queues (some of them can be temporary) and you don't want to gather rabbitmq_queue at all, you can apply queues_exclude = ["*"]. But the telegraf will make request to the RabbitMQ API to grab all these queues stats anyway. ~1Mb will be requested in every collecting interval, it causes timeouts from time to time and overloads network. Not only I have faced this issue, @kerams seems to have faced this issue as well (see #3701).

[kerams]

@ildarsv Why not just check if queues_exclude contains *, in which case you don't query the API at all?

[ildarsv]

Alright, I like this way too, let me do it

[ildarsv]

@danielnelson I will appreciate if you make some comment/review for this PR when you have time.