Release RPyC 3.4.2

- Fix ``export_function`` on python 3.6

Release rpyc 3.4.1

* Fix issue high-cpu polling (tomerfiliba-org#191,tomerfiliba-org#218)
* Fix filename argument in logging (tomerfiliba-org#197)
* Improved log messages (tomerfiliba-org#191,tomerfiliba-org#204)
* Drop support for python 3.2 and py 2.5

Release rpyc 3.4.0

realeasing 3.3

remove six

scripts/rpyc_classic was moved

select.error fixes

releasing 3.2.0

fixing build

BgServingThread works like charm