Create SQL schema for RdeRevision (#835)

* Create SQL schema for RdeRevision

* Split RdeRevision IDs into three separate DB fields as unified pkey

* Rename variable

* Merge remote-tracking branch 'origin/master' into rdeRevision

* Rename variable in one other location

* Implement no-op toDatastore/Sql for RdeRevision

* Responses to CR

* Merge remote-tracking branch 'origin/master' into rdeRevision

* Use a date for the date column

* Fix exception messages in tests

* Regen diagram to fix the test

* Use assignment in static factory methods

* Merge remote-tracking branch 'origin/master' into rdeRevision

db/src/main/resources/sql/flyway/V66__create_rde_revision.sql

@@ -0,0 +1,22 @@
+-- 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 "RdeRevision" (
+   tld TEXT NOT NULL,
+   mode TEXT NOT NULL,
+   date date NOT NULL,
+   update_timestamp timestamptz,
+   revision int4 NOT NULL,
+   PRIMARY KEY (tld, mode, date)
+);