Added setup.py and prototype for a test.

setup.py

+from setuptools import setup, find_packages
+
+setup(
+    name="grext",
+    version="0.1.0",
+    packages=find_packages(),
+    install_requires=["numpy"],
+    author="Michele Nottoli",
+    description="Tools for generating new guesses for SCF calculations.",
+    classifiers=[
+        "Programming Language :: Python :: 3",
+        "License :: OSI Approved :: MIT License",
+        "Operating System :: OS Independent",
+    ],
+)

tests/test_grassmann.py

+import os
+import sys
+import numpy as np
+
+sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
+import grext
+
+def test_grassmann():
+    grext.Extrapolator(10, 10, 10, 10)