* Add Micronaut Sample
* Updated Dockerfile to use AdoptOpenJDK.
* renamed directory
* removed .factorypath
* ignore .factorypath
* removed PORT from Dockerfile
updated `application.yml` to respect port env var, and using a reasonable default
* renamed helloworld-micronaut to helloworld-java-micronaut
* Added frontmatter _index.md, and added link in samples/README.md
* small typo and PR#1202
Graeme Rocher