add migrations

migrations/003-device-events.js

@@ -0,0 +1,17 @@
+'use strict';
+
+var db = require('./db');
+
+exports.up = function(next){
+  db.query('CREATE TABLE machine_events ( ' +
+    'id uuid PRIMARY KEY, ' +
+    'device_fingerprint text NOT NULL, ' +
+    'event_type text NOT NULL, ' +
+    'note text, ' +
+    'device_time bigint NOT NULL, ' +
+    'created timestamp NOT NULL DEFAULT now() )', next);
+};
+
+exports.down = function(next){
+  next();
+};