Improving multiprocessing

[casabre]

The previous PR #148 introduced some errors and thus, the commits were reverted. In order to provide multiprocessing functionality, this new PR will be opened.

[casabre]

@dixudx I used your ThreadPool implementation and extended it by another ThreadPool in the base.py file. Now, it is really fast compared to the previous implementation. I guess, the ProcessPool was an overkill regarding spawning up.

[dixudx]

All look good to me, except tests for Python 2.7.

Keyword with will call pool.terminate() (i.e. __exit__) automatically , while for Python 2.7 pool.close() should be called instead.

@casabre I think we may need a Python decorator to better handle this compatibility.

[dixudx]

We have decided that January 1, 2020, was the day that we sunset Python 2.

I wonder whether we still need to support rtcclient on Python 2.7.

[casabre]

I wonder whether we still need to support rtcclient on Python 2.7.

I just wanted to ask the same. I don't know about the current real utilization of Python 2.7 but it's been a while since its end of life and thus, I would keep the effort low and would make the rtcclient future-proof 😊.

[casabre]

@dixudx PR is ready for v0.8.1 😃