Rename recent schema upgrade file.

(There were no schema changes between 1.5 and 1.6)

docs/schema-upgrade-1.6-1.7.sql

@@ -0,0 +1,25 @@
+BEGIN;
+
+CREATE TABLE volume (
+        id SERIAL NOT NULL PRIMARY KEY,
+        name TEXT UNIQUE NOT NULL
+) WITHOUT OIDS;
+
+INSERT INTO volume (id, name) VALUES (0, 'DEFAULT');
+
+ALTER TABLE build ADD COLUMN volume_id INTEGER REFERENCES volume (id);
+UPDATE build SET volume_id = 0;
+ALTER TABLE build ALTER COLUMN volume_id SET NOT NULL;
+
+CREATE TABLE tag_updates (
+        id SERIAL NOT NULL PRIMARY KEY,
+        tag_id INTEGER NOT NULL REFERENCES tag(id),
+        update_event INTEGER NOT NULL REFERENCES events(id) DEFAULT get_event(),
+        updater_id INTEGER NOT NULL REFERENCES users(id),
+        update_type INTEGER NOT NULL
+) WITHOUT OIDS;
+
+CREATE INDEX tag_updates_by_tag ON tag_updates (tag_id);
+CREATE INDEX tag_updates_by_event ON tag_updates (update_event);
+
+COMMIT;