After #2167 is merged we need to update the examples in the docs with the following changes:

• http.params -> http.request.params
• http.code -> http.response.code
• http.phrase -> http.response.phrase
• http.request_headers -> http.request.headers
• http.response_headers -> http.response.headers
• http.content_length -> http.response.headers["content-length"]
• http.content_type -> http.response.headers["content-type"]

cc-ed @dedemorton