Adding Traefik IngressRoute support

[abs0lom]

I use Traefik as Ingress Controller with the IngressRoute kind provided by his CRD.

This implementation is not complete, but sufficient for my case.

You're welcome to comment this PR about missing functionalities, I'll update my work to provide more generic stuff about Traefik IngressRoute feature.

[fastlorenzo]

@abs0lom the chart has been through a big refactor, could you maybe rebase and propose new change?

[abs0lom]

I just migrated my Mailu stack to version 1.2.0. As the migration was a big deal, I used the native ingress resource for the moment, using the Traefik specific annotations.

This will allow me to propose a better and more complete work than my first implementation. I will start by making a list of desirable features for traefik CRDs.

I'll work on it this weekend!

[DrPsychick]

I would argue that the Mailu Helm Chart should not support/include all kinds of 3rd party CRD objects.
A custom deployment could, for example, consist of a chart containing the IngressRoute and the Mailu Helm Chart as a dependency. Or the IngressRoute is simply applied separately to Kubernetes.

@fastlorenzo @promasu if you agree, I will close this.

[fastlorenzo]

I think we should support httproute and gateway, which would allow broader usage.
Maybe we could have a generic extraResources array in the values, that would be rendered as is, so people can include custom resources without pain

[DrPsychick]

Yes, that's a great idea. Gateway-api is coming either way.

So I'll close this and open an issue to support gateway-api.