Record the output from loading new revisions to the database

So that it can easily be shown through the web interface. There's two tables
being used. One which temporarily stores the output as it's output while the
job is running, and other which stores the whole log once the job has
finished.

sqitch/deploy/load_new_guix_revision_job_logs.sql

@@ -0,0 +1,16 @@
+-- Deploy guix-data-service:load_new_guix_revision_job_logs to pg
+
+BEGIN;
+
+CREATE TABLE load_new_guix_revision_job_log_parts (
+    id integer NOT NULL,
+    job_id integer NOT NULL,
+    contents text NOT NULL
+);
+
+CREATE TABLE load_new_guix_revision_job_logs (
+    job_id integer PRIMARY KEY REFERENCES load_new_guix_revision_jobs (id),
+    contents text NOT NULL
+);
+
+COMMIT;