Why does not the Req method of Session be provided?

[elonzh]

This project is convenient for simply requesting and response handling, but it's tricky if you want to hook the request will be sent or the response we received.

Here are my suggestions:

• Add a Req method for Session
• Export buildRequest and send request in other place, like requests in Python
• Export buildResponse for external response packging

[levigross]

That is a good idea, I am thinking on adding some hooks to RequestOptions to do that