Add sql schema and entity class for ClaimsList (#227)

db/src/main/resources/sql/schema/claims_list.sql

@@ -0,0 +1,27 @@
+-- Copyright 2019 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 `ClaimsList` (
+  revision_id BIGSERIAL NOT NULL,
+  creation_timestamp TIMESTAMPTZ NOT NULL,
+  PRIMARY KEY (revision_id)
+);
+
+CREATE TABLE `ClaimsEntry` (
+  revision_id BIGSERIAL NOT NULL,
+  claim_key TEXT NOT NULL,
+  domain_label TEXT NOT NULL,
+  PRIMARY KEY (revision_id, domain_label),
+  FOREIGN KEY (revision_id) REFERENCES `ClaimsList`(revision_id)
+);