moved Context and ContextHelper to javaposse.jobdsl.dsl
better JavaDoc
[JENKINS-25482] Support for extended email triggers Always, FirstUnstable, FixedUnhealthy, SecondFailure, StatusChanged
cleanup
Merge branch 'ext-email'
Add ConcurrentModificationException workaround.
Merge pull request #336 from CoreMedia/context

Moved Context and ContextHelper to javaposse.jobdsl.dsl
added Troubleshooting section, changed some wording
Merge branch 'concurrentmodificationexception'
added closure for HTML report details
Merge branch 'JENKINS-26071'

Conflicts:
	job-dsl-core/src/main/groovy/javaposse/jobdsl/dsl/helpers/publisher/HtmlReportContext.groovy