Add image_username and image_password to charms

This commit will allow us to pull images for OSM components from a
private docker registry, protected with username and password

Change-Id: I854028d6abbb1cae07c61692ba73d08825763212
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/installers/charm/ui-k8s/reactive/spec_template.yaml b/installers/charm/ui-k8s/reactive/spec_template.yaml
index b63c210..4b3eef3 100644
--- a/installers/charm/ui-k8s/reactive/spec_template.yaml
+++ b/installers/charm/ui-k8s/reactive/spec_template.yaml
@@ -14,7 +14,10 @@
 version: 2
 containers:
   - name: %(name)s
-    image: %(docker_image)s
+    imageDetails:
+      imagePath: %(image)s
+      username: %(image_username)s
+      password: %(image_password)s
     ports:
     - containerPort: %(advertised-port)s
       protocol: TCP