Implement version checking

db/00-version.sql

@@ -0,0 +1,11 @@
+CREATE TABLE version (
+	major INT NOT NULL,
+	minor INT NOT NULL,
+	PRIMARY KEY (major,minor)
+);
+
+CREATE OR REPLACE FUNCTION get_version() RETURNS VARCHAR
+	AS $$SELECT major || '.' || minor FROM version $$
+	LANGUAGE SQL;
+
+INSERT INTO version (major,minor) VALUES (0,1);