Adding a notification step if docker-publish job fails

Change-Id: I0a81896fe67b3d9eeb1901ceb21113c6833e459f
diff --git a/jjb/pipeline/docker-publish.groovy b/jjb/pipeline/docker-publish.groovy
index 9b2e74b..32299f8 100644
--- a/jjb/pipeline/docker-publish.groovy
+++ b/jjb/pipeline/docker-publish.groovy
@@ -114,5 +114,8 @@
       archiveArtifacts artifacts: 'docker-*.log', fingerprint: true
       deleteDir()
     }
+    failure {
+      step([$class: 'Mailer', notifyEveryUnstableBuild: true, recipients: "${params.maintainers}", sendToIndividuals: false])
+    }
   }
 }