commands/postgres: Upgrade the data base schema to v1.3

Upgrade the database schema to reflect the additions of directory
artifacts and the missing TargetInfo property.

wa/commands/postgres_schemas/postgres_schema.sql

@@ -1,4 +1,4 @@
---!VERSION!1.2!ENDVERSION!
+--!VERSION!1.3!ENDVERSION!
 CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
 CREATE EXTENSION IF NOT EXISTS "lo";
 
@@ -96,6 +96,7 @@ CREATE TABLE Targets (
     android_id text,
     _pod_version int,
     _pod_serialization_version int,
+    system_id text,
     PRIMARY KEY (oid)
 );
 
@@ -164,6 +165,7 @@ CREATE TABLE Artifacts (
     kind text,
     _pod_version int,
     _pod_serialization_version int,
+    is_dir boolean,
     PRIMARY KEY (oid)
 );
 

wa/commands/postgres_schemas/postgres_schema_update_v1.3.sql

@@ -0,0 +1,3 @@
+ALTER TABLE targets ADD COLUMN system_id text;
+
+ALTER TABLE artifacts ADD COLUMN is_dir boolean;