Simple blocking API for gevent usage?

[davidkhess]

Is your feature request related to a problem? Please describe.
I'm using gevent and would like to use this library. Given that coms take place over a unix domain socket, a simple blocking interface would work best. But there doesn't appear to be one?

Describe the solution you'd like
I'd like a simple blocking interface that I can use with gevent.

Additional context
I may be interested in providing a PR to implement gevent compatibility.