Employeeへ帳票機能追加
参考
http://blog.scimpr.com/2012/10/22/rails3%E3%81%A7%E5%B8%B3%E7%A5%A8%E5%8D%B0%E5%88%B7%E3%82%92%E8%A9%A6%E3%81%99%EF%BD%9Ethinreports/