Allow Postman contract-testing support using ensemble design

[JulienBreux]

Description

This pull-request is designed to iso current developments for JS and Java.

• [x] Add ensemble sub-package
• [x] Add ensemble sub-package tests
• [x] Refactor test/helper
• [x] Update README
• [x] Add ensemble Microcks image customization
• [x] Add ensemble Postman image customization
• [x] Finalize ensemble test with good and bad implem

Related issue(s)

• https://github.com/microcks/microcks-testcontainers-go/issues/7

[lbroudoux]

Just a suggestion: shouldn't we keep ensemble as a top-level concept just close to microns.go (and maybe rename it as microns-ensemble.go ?) and then move postman and async-minion containers in their own sub-packages ?

[JulienBreux]

Ok, no pb, I'll move to ensemble.go. And change some signatures.

[JulienBreux]

Just a suggestion: shouldn't we keep ensemble as a top-level concept just close to microns.go (and maybe rename it as microns-ensemble.go ?) and then move postman and async-minion containers in their own sub-packages ?

The main problem I see is options in the same package area (eg WithNetwork ... etc) What's real problem to use an import like import "microcks.io/testcontainers-go/ensemble vs import "microcks.io/testcontainers-go" in your opignon?

[lbroudoux]

No, no issue here. I was unaware of this constraint in Go and was much more thinking about having a similar approach between the different languages where possible. But I agree that we should also stick to language constraints, idioms and ways of doing things. I trust you for the Go Lang part 💪

[lbroudoux]

Thank you very much for the quick changes @JulienBreux! That's a great contribution!