Support of Python 2.7

[lfarv]

For how long do we need to support python 2.7?
It's now more that one year that it reached end-of-life…

Dropping 2.7 would allow to use some interesting new constructs.
@willrogers , what's your advice?

[swhite2401]

At ESRF we have now fully migrated to python3 so this should not be a problem for us

[willrogers]

I think we should drop support for Python 2. It would be tidy to make one more release now before we do it.

The move from Travis CI to Github Actions means that the process of releasing to PyPI will need to be changed. I will do this, but I am very busy at work at the moment and have a baby due in a few weeks!

[lnadolski]

At SOLEIL, the migration to Python 3 is not done yet.
Maybe it is the case in other labs
Regards,

Laurent.

[willrogers]

@lnadolski you could still use PyAT versions up to 0.1, which I just released. We are considering dropping Python 2.7 on the master branch - see #234 (comment)

cc @lfarv

[lfarv]

Python 2.7 has been marked "End-of-life" more than one year ago! I think it makes sense to stop python 2 support at version 0.1.0. In addition, with virtual environments, it's easy to run AT with python 3 while keeping everything else on an older version.

[matsievskiysv]

It might be a good idea add some tag to the last python2 compatible version.