Allowing to configure registration backends in chart

chart/files/registrar-config.yaml

@@ -68,9 +68,6 @@ backends:
               {{- end }}
           {{- end }}
         {{- end }}
-  - type: pycsw
-    filter:
-    kwargs:
-      instance_base_path: /var/www/pvs/dev
-      instance_name: pvs_instance
-      mapping:
+  {{- range .Values.config.registrar.backends | default list }}
+  -{{ toYaml . | nindent 6 }}
+  {{- end }}