Easy logging

[appsforartists]

Reqwest should support logging levels. At a minimum, I'd like to be able to tell it:

• Log nothing
• Log method and URL
  • with headers & cookies
• Log response before parsing

It could be as simple as:

Reqwest.logLevel = ReqwestLogLevel.SMALL_REQUEST;

// where

ReqwestLogLevel = {
    "NONE":               0,
    "SMALL_REQUEST":     10,
    "BIG_REQUEST":       20,
    "BIG_RESPONSE":     110
}