Add reference to docker extension

[FaustXVI]

Overview

Add a link to an extension that allow the user to start docker containers from their tests.

JUnit5-Docker has just been pushed to maven contral as a release candidate for version 1.0.0.
It only implements one feature : start one container from your test. The idea is to have something that works early. More features to come.

I think it will be a very useful extension and adding the reference to the documentation would show that an extension can do something else than integrate with another framework.

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[jbduncan]

Have you considered making your proposal on junit-io? :)

[nipafx]

@FaustXVI The Docker extension looks pretty cool, great idea!

I started JUnit Io to collect small(ish) extensions and breed ideas but didn't get very far yet. Your extension seems to be pretty well-defined and self-contained, so it makes sense to be its own library. But if you see value in merging into another project, I'm happy to discuss that.

[FaustXVI]

@nicolaiparlog That's a great initiative !
For the moment, I do agree that, since we have a quite well-defined scope it totally make sens to keep it separated.
Nonetheless, I keep the idea in mind, maybe I'll change my mind someday :)

[smoyer64]

@FaustXVI

This seems like one of those situations where @BeforeSuite/@AfterSuite would be ideal when you want the container to be used for more than one class. In any case, it looks awesome. Looking at your commits, I see that you're adding the reference to the users guide ... there's an open issue with the subject "Maintain list of third-party TestEngines and Extensions" #297 that you might want to look at.

[FaustXVI]

Using @BeforeSuite and @AfterSuite is great idea ! I'll add it to my issues.
I'll definitely look at #297 , thanks !

[sbrannen]

closing this issue since it will be addressed in #297.