Add the possibility of registering custom queue types

[luos]

Proposed Changes

With the addition of the queue_type API the ability to create custom queue types became possible. With this small change plugin creators can implement their own special queues without interfering with core RabbitMQ functionality.

We think this would be a really useful addition to extend RabbitMQ.

Let us know what you think.

Types of Changes

What types of changes does your code introduce to this project?
Put an x in the boxes that apply

• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)
• Build system and/or CI

[michaelklishin]

@luos this looks good. Out of curiosity, can you share what you plan on doing with this?

[michaelklishin]

Enough of our team members agreed to adopting this, ideally starting with 3.13.0.

[luos]

Great news, thank you. We experimented some more with this and it works but needs some more tweaks to be a fully working solution, we plan to open a new PR with some additions next week.

To answer your original question, we are just experimenting with some special queue types, for example fully in memory queues and conditional consumption of messages from certain queues.