JENKINS-21328 - support test stability publisher (documentation update)
Merge branch 'JENKINS-21328' of https://github.com/kmoens/job-dsl-plugin
into JENKINS-21328

Conflicts:
	docs/Job-DSL-Commands.md
	docs/Job-reference.md
	job-dsl-core/src/main/groovy/javaposse/jobdsl/dsl/helpers/publisher/PublisherContext.groovy
	job-dsl-core/src/test/groovy/javaposse/jobdsl/dsl/helpers/publisher/PublisherHelperSpec.groovy