improve response object

**current**

1. send([responseCode,] responseObject)
2. reject([responseCode,] responseObject)
3. end()
4. setHeader(type, value)
5. headersSent ? (boolean)

**need**

1. setHeaders(array of objects)
2. status(statusCode) -- a method which could be chained before send or reject.
3. headers(array of objects) -- a method which could be chained before send or reject.
4. redirect()
