[ecasound] pyecasound Python 3 support

[Kristaps K. <kri...@gm...>]

Hi,

I've started to port native Python ECI to Python 3.x as I'm migrating
my project as well.

What has been done:
* ecacontrol module works
* test1_stresstest.py, test2_stresstest.py tests also work

What hasn't been done yet:
* ecamonitor

Other:
I'd like to clean up ecacontrol a bit more, format code to conform to
PEP 8 standard. Afterwards I'd like to convert test*_stresstest.py
scripts to nose2 tests.

Also what is the state of native C implementation? As far as I
understand that has been deprecated for a while.

Current implementation has been tested with Python 2.7.11 and 3.5.1.

Source (`devel-python3` branch):
https://github.com/skakri/ecasound/compare/devel-python3?expand=1

Looking forward to your comments,

Kristaps Karlsons