Document how to release jboss-parent

[bstansberry]

Releasing jboss-parent has some subtleties because its nxrm3-maven-plugin configuration is designed for the benefit of child projects, and not for its own use. The pom itself sets both 'nexus.repository.staging' and 'nexus.repository.release' to 'releases', which is not the intended repo for this project. So to release jboss-parent you need to override its own settings via -D.

We should document this or it's almost certain to go wrong.

Perhaps this could go in the README, but this project needs a CONTRIBUTING.md to meet Commonhaus requirements, so perhaps we can cover this there. The README is quite reasonably focused on how to use jboss-parent, so mixing in stuff about how to develop it would be confusing or result in that content being overlooked. If we covered this stuff in CONTRIBUTING, then README after the "What is it?" section could have a quick side note stating that if you are looking for information about developing jboss-parent, look in CONTRIBUTING.

Anyway, to deploy jboss-parent:

1. Deploy to a staging repo so you can validate your work:

mvn clean deploy -Pjboss-release -Dnexus.repository.staging=wildfly-staging

The above assumes this project will use the wildfly-staging repo for this. There's discussion of that general topic in #wildfly-developers > Nexus Sharing a Staging Repo vs Distinct Staging Repos

2. Once you're sure the release is good, "promote" it to the "jboss-common" repo

mvn nxrm3:staging-move -Dnexus.repository.staging=wildfly-staging -Dnexus.repository.release=jboss-common

NOTE: If this project decided to forego using a staging repo, then step 2 could be skipped and step 1 becomes:

mvn clean deploy -Pjboss-release -Dnexus.repository.release=jboss-common

Note that in this case the -D property to set is 'nexus.repository.release' not 'nexus.repository.staging'.