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/config/RegistryConfig.java

@@ -44,6 +44,13 @@ public interface RegistryConfig {
    */
   public String getSnapshotsBucket();
 
+  /**
+   * Returns the Google Cloud Storage bucket for storing exported domain lists.
+   *
+   * @see com.google.domain.registry.export.ExportDomainListsAction
+   */
+  public String getDomainListsBucket();
+
   /**
    * Returns the BigQuery dataset for storing directly imported datastore snapshots.
    *