Add NG-UI Charm

Change-Id: Id94b6e0383994580c2b11ab66a44f7c197cb7412
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/.gitmodules b/.gitmodules
index 16acbbf..1fc8abd 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -11,7 +11,9 @@
 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #   See the License for the specific language governing permissions and
 #   limitations under the License.
-
 [submodule "installers/charm/pla/mod/operator"]
 	path = installers/charm/pla/mod/operator
 	url = https://github.com/canonical/operator
+[submodule "installers/charm/ng-ui/mod/operator"]
+	path = installers/charm/ng-ui/mod/operator
+	url = https://github.com/canonical/operator