Progress API

[dereke]

There is currently no way to get progress information when making large requests.

Httpism should use this API:

const http = httpism.client({progress: handleProgress})
...
http.post('/blah', bigRequest)

handleProgress would be a function that has one argument:

{
  type: 'download|upload'
  total: 1000,
  current: 100,
  request: ...,
  options: ...,
  response: ...
}

You could also get progress on individual requests:

http.post('/blah', bigRequest, {progress: handleProgress})