add pyproject.html

I read pypa/setuptools#1698, and a side effect
of source root not being in sys.path is mentioned: probably that is
related to PyInstaller and other things so I left a commented out thing
in setup.py b/c odds seem high that will effect us.

pyproject.toml

@@ -0,0 +1,3 @@
+[build-system]
+requires = ["setuptools >= 40.6.0", "wheel"]
+build-backend = "setuptools.build_meta"

setup.py

@@ -5,6 +5,9 @@
 with open("README.md", "r") as fh:
     long_description = fh.read()
 
+# TODO: "stop importing things from the local path" or use this workaround:
+#sys.path.insert(0, os.dirname(__file__))
+
 # This directory
 dir_setup = os.path.dirname(os.path.realpath(__file__))