Drop support for Python 2

[mrbean-bremen]

Support for Python ends in January 2019, and many projects are committed to drop support at that date or before.
I propose to officially drop support for Python 2 in pyfakefs 4.0, which may be released somewhere at the start of 2019 or even earlier, and leave open the possibility for updates to a previous version in case a fix is really needed for Python 2. I would also drop support of the old deprecated API with the same version.
This will make it possible to better support Python 3 and have cleaner code (I already made a branch some time ago where I tried that out).
What do you think?

[hugovk]

Sounds good. Python 3.4 is also EOL, so that can be dropped already.

[mrbean-bremen]

Yes, Python 3.4 will certainly be dropped with the next major release, though that is not such a big deal as Python 2 ;)

@jmcgeheeiv - what do you think?

[jmcgeheeiv]

Things will be much easier to support without Python 2. I leave Python 3.4 to your discretion.

[mrbean-bremen]

Thanks - I will add pyfakefs to the Python 3 statement page in this case (unfortunately, we have no icon...) (EDIT: done) and leave this issue open for reference. Probably will add a note in the release notes, too.

[mrbean-bremen]

Python 2 support is now dropped in master, with the last release out that still supports it.
Closing.