Add scrap tool for populating required registrar fields

This tool finds all registrars that have a null name, or a null localizedAddress field, and populates them as follows:

- The registrar's name is updated to its clientId
- The registrar's empty localizedAddress fields are replaced with fake data

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=155739946

java/google/registry/tools/RegistryTool.java

@@ -15,6 +15,7 @@
 package google.registry.tools;
 
 import com.google.common.collect.ImmutableMap;
+import google.registry.tools.javascrap.PopulateNullRegistrarFieldsCommand;
 import google.registry.tools.javascrap.RemoveDomainTransferDataCommand;
 import google.registry.tools.javascrap.RemoveIpAddressCommand;
 
@@ -97,6 +98,7 @@ public final class RegistryTool {
           .put("logout", LogoutCommand.class)
           .put("make_billing_tables", MakeBillingTablesCommand.class)
           .put("pending_escrow", PendingEscrowCommand.class)
+          .put("populate_null_registrar_fields", PopulateNullRegistrarFieldsCommand.class)
           .put("publish_detail_report", PublishDetailReportCommand.class)
           .put("registrar_activity_report", RegistrarActivityReportCommand.class)
           .put("registrar_contact", RegistrarContactCommand.class)