Using global for images on all master pods and cleaning up unused files

Change-Id: I51deccd5270d874f4a34756bbce02c13364f0ce2
diff --git a/kubernetes-configs/voltha/dt-berlin-pod.yml b/kubernetes-configs/voltha/dt-berlin-pod.yml
index 86d17db..4723038 100644
--- a/kubernetes-configs/voltha/dt-berlin-pod.yml
+++ b/kubernetes-configs/voltha/dt-berlin-pod.yml
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-defaults:
+global:
   image_tag: master
   image_pullPolicy: Always