Add Streaming to Crawlbot

[Swader]

A crawlbot's job constantly enhances the resultset with new data. Ergo, when fetching the resultset, it's always different unless the job is done or paused.

Since the library depends on Guzzle, perhaps consider using streams?

To keep in mind: stopping the stream if job is paused. Would require re-checking job status? Open for discussion.

[Swader]

Client no longer depends on Guzzle. Makes it more versatile and flexible, but brings streams into questions perhaps.