Add [] to export domain lists to GCS

The ExportDomainListsAction [] has a cron entry that runs it twice per day.  It exports one flat text file per real (non-test) TLD to the "{project-id}-domain-lists" bucket in Google Cloud Storage, overwriting the existing ones in place.  Each file is a newline-delimited list of active (non-deleted) domains in that TLD.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=116767987

java/com/google/domain/registry/env/common/backend/WEB-INF/web.xml

@@ -364,6 +364,15 @@
     <url-pattern>/_dr/task/syncGroupMembers</url-pattern>
   </servlet-mapping>
 
+  <servlet>
+    <servlet-name>export-domain-lists</servlet-name>
+    <servlet-class>com.google.domain.registry.module.backend.BackendServlet</servlet-class>
+  </servlet>
+  <servlet-mapping>
+    <servlet-name>export-domain-lists</servlet-name>
+    <url-pattern>/_dr/task/exportDomainLists</url-pattern>
+  </servlet-mapping>
+
   <!--  Mapreduce to delete the specified contact resource if it is not referenced by any domains. -->
   <servlet>
     <description>