add serials to machine logging

migrations/1514981004673-add_serial_to_logs.js

@@ -0,0 +1,10 @@
+const db = require('./db')
+
+exports.up = function (next) {
+  const sql = ['alter table logs add column serial integer not null default 0']
+  db.multi(sql, next)
+}
+
+exports.down = function (next) {
+  next()
+}