Add ubuntu-18.04 executor to ONOS Jenkins

Change-Id: I7ac1878e9581b955c51b7c9a949cb62f6976432f
diff --git a/jjb/ci-management/ci-management.yaml b/jjb/ci-management/ci-management.yaml
index 1720721..2e6ae75 100644
--- a/jjb/ci-management/ci-management.yaml
+++ b/jjb/ci-management/ci-management.yaml
@@ -11,6 +11,7 @@
           platforms:
             - 'centos-7'
             - 'ubuntu-16.04'
+            - 'ubuntu-18.04'
           templates:
             - basebuild
 
diff --git a/packer/vars/ubuntu-18.04.json b/packer/vars/ubuntu-18.04.json
new file mode 100644
index 0000000..37e4ba7
--- /dev/null
+++ b/packer/vars/ubuntu-18.04.json
@@ -0,0 +1,10 @@
+{
+  "source_ami_filter_name": "*ubuntu*18.04*",
+  "source_ami_filter_owner": "aws-marketplace",
+  "source_ami_filter_product_code": "3iplms73etrdhxdepv72l6ywj",
+  "ssh_user": "ubuntu",
+
+  "distro": "Ubuntu 18.04",
+  "arch": "x86_64",
+  "cloud_user_data": "provision/null_data.sh"
+}