[JENKINS-19162] Return the actual label that represents the node instead of its display name. This fixes the selection of the master node, whose display name is "Jenkins".
Merge pull request #2 from wgreven-ibr/JENKINS-19162

Fix for [JENKINS-19162] elastic-axis: a dummy "Jenkins" node is added to the list of candidates
[maven-release-plugin] prepare release elastic-axis-1.2
[maven-release-plugin] prepare for next development iteration