Add SQL schema for DelegationSignerData (#713)

* Add SQL schema for DelegationSignerData

* Remove join table

* Rebased on HEAD

* Rebase on head

db/src/main/resources/sql/flyway/V63__add_schema_for_ds_data.sql

@@ -0,0 +1,29 @@
+-- Copyright 2020 The Nomulus Authors. All Rights Reserved.
+--
+-- Licensed under the Apache License, Version 2.0 (the "License");
+-- you may not use this file except in compliance with the License.
+-- You may obtain a copy of the License at
+--
+--     http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS,
+-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+-- See the License for the specific language governing permissions and
+-- limitations under the License.
+
+create table "DelegationSignerData" (
+    domain_repo_id text not null,
+    key_tag int4 not null,
+    algorithm int4 not null,
+    digest bytea not null,
+    digest_type int4 not null,
+    primary key (domain_repo_id, key_tag)
+);
+
+create index IDXhlqqd5uy98cjyos72d81x9j95 on "DelegationSignerData" (domain_repo_id);
+
+alter table if exists "DelegationSignerData"
+   add constraint FKtr24j9v14ph2mfuw2gsmt12kq
+   foreign key (domain_repo_id)
+   references "Domain";