Adding owners file for openshift_logging_defaults role

roles/openshift_logging_defaults/OWNERS

@@ -0,0 +1,10 @@
+# approval == this is a good idea /approve
+approvers:
+  - jcantrill
+  - ewolinetz
+  - sdodson
+# review == this code is good /lgtm
+reviewers:
+  - jcantrill
+  - ewolinetz
+  - richm