Send email on publish-imagebuilder job failures

Change-Id: Ib8b84db5ed9a762f66ab7f10a0e22100b68dc5d9
diff --git a/jjb/pipeline/imagebuilder.groovy b/jjb/pipeline/imagebuilder.groovy
index deee937..a8636ea 100644
--- a/jjb/pipeline/imagebuilder.groovy
+++ b/jjb/pipeline/imagebuilder.groovy
@@ -75,5 +75,10 @@
       archiveArtifacts artifacts: 'ib_actions.yml, ib_graph.dot, ib_logs/*', fingerprint: true
       deleteDir()
     }
+    failure {
+      emailext (
+        to: "${params.failureEmail}"
+      )
+    }
   }
 }