Integrate transaction persistence into JpaTM (#717)

* Integrate transaction persistence into JpaTM

Store the serialized transaction whenever we commit from the JPA transaction
manager.  This change also adds:

-   The Transaction table.
-   The TransactionEntity which is stored in it.
-   Changes to the test infrastructure to register the TransactionEntity for
    tests where we don't load the nomulus schema.
-   A new configuration variable to allow us to turn the transaction
    persistence functionality on and off (default is "off").

* Changes for review.

* Incremented sequence number of flyway file

db/src/main/resources/sql/flyway/V42__add_txn_table.sql

@@ -0,0 +1,19 @@
+-- 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 "Transaction" (
+   id  bigserial not null,
+    contents bytea,
+    primary key (id)
+);

db/src/main/resources/sql/schema/db-schema.sql.generated

@@ -494,6 +494,12 @@ create sequence history_id_sequence start 1 increment 1;
         tld text not null,
         primary key (id)
     );
+
+    create table "Transaction" (
+       id  bigserial not null,
+        contents bytea,
+        primary key (id)
+    );
 create index IDXih4b2tea127p5rb61gje6e1y2 on "BillingCancellation" (registrar_id);
 create index IDX2exdfbx6oiiwnhr8j6gjpqt2j on "BillingCancellation" (event_time);
 create index IDXqa3g92jc17e8dtiaviy4fet4x on "BillingCancellation" (billing_time);

db/src/main/resources/sql/schema/nomulus.golden.sql

@@ -770,6 +770,35 @@ CREATE SEQUENCE public."SafeBrowsingThreat_id_seq"
 ALTER SEQUENCE public."SafeBrowsingThreat_id_seq" OWNED BY public."Spec11ThreatMatch".id;
 
 
+--
+-- Name: Transaction; Type: TABLE; Schema: public; Owner: -
+--
+
+CREATE TABLE public."Transaction" (
+    id bigint NOT NULL,
+    contents bytea
+);
+
+
+--
+-- Name: Transaction_id_seq; Type: SEQUENCE; Schema: public; Owner: -
+--
+
+CREATE SEQUENCE public."Transaction_id_seq"
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1;
+
+
+--
+-- Name: Transaction_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
+--
+
+ALTER SEQUENCE public."Transaction_id_seq" OWNED BY public."Transaction".id;
+
+
 --
 -- Name: BillingCancellation billing_cancellation_id; Type: DEFAULT; Schema: public; Owner: -
 --
@@ -833,6 +862,13 @@ ALTER TABLE ONLY public."ReservedList" ALTER COLUMN revision_id SET DEFAULT next
 ALTER TABLE ONLY public."Spec11ThreatMatch" ALTER COLUMN id SET DEFAULT nextval('public."SafeBrowsingThreat_id_seq"'::regclass);
 
 
+--
+-- Name: Transaction id; Type: DEFAULT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public."Transaction" ALTER COLUMN id SET DEFAULT nextval('public."Transaction_id_seq"'::regclass);
+
+
 --
 -- Name: BillingCancellation BillingCancellation_pkey; Type: CONSTRAINT; Schema: public; Owner: -
 --
@@ -1001,6 +1037,14 @@ ALTER TABLE ONLY public."Spec11ThreatMatch"
     ADD CONSTRAINT "SafeBrowsingThreat_pkey" PRIMARY KEY (id);
 
 
+--
+-- Name: Transaction Transaction_pkey; Type: CONSTRAINT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public."Transaction"
+    ADD CONSTRAINT "Transaction_pkey" PRIMARY KEY (id);
+
+
 --
 -- Name: RegistryLock idx_registry_lock_repo_id_revision_id; Type: CONSTRAINT; Schema: public; Owner: -
 --