Add setup.py

[ghost]

Not tested: installation (should work). Tested: build (I think the script part needs a minor edit, I'm rusty on the details or we set it automatically in pkgsrc and other systems).

Failing: some tests, but that's what I expected with alpha software on a non-mainstream operating system etc (entirely different issue.. details below for reference:

python3.7 setup.py test
running pytest
running egg_info
writing pyrs.egg-info/PKG-INFO
writing dependency_links to pyrs.egg-info/dependency_links.txt
writing top-level names to pyrs.egg-info/top_level.txt
writing manifest file 'pyrs.egg-info/SOURCES.txt'
running build_ext
============================= test session starts ==============================
platform netbsd8 -- Python 3.7.3, pytest-4.4.2, py-1.8.0, pluggy-0.11.0
rootdir: /home/ng0/src/pyrs
collected 53 items                                                             

pyrs/tests/test_analysis.py .......                                      [ 13%]
pyrs/tests/test_clike.py .                                               [ 15%]
pyrs/tests/test_context.py F........                                     [ 32%]
pyrs/tests/test_scope.py ..                                              [ 35%]
pyrs/tests/test_tracer.py .....FFF..FF..                                 [ 62%]
pyrs/tests/test_transpiler.py FFFFFFFFFFFFFFFFFFFF                       [100%]

=================================== FAILURES ===================================

[ghost]

It would be useful to know which rust version you develop this against (excluding my rust version as the source of test failures)

[konchunas]

Apparently these tests are just a legacy code from py14 project which is what "pyrs" is based on. I hope to fix them one day and even add new, relevant ones. Regarding Rust version pretty much anything above 1.2 would suffice as it is not generating anything specific to new versions.

Thank you for your contribution!