Add setup.py, proper CLI interface.

setup.py

@@ -0,0 +1,17 @@
+from distutils.core import setup
+
+setup(
+    name='NextAction',
+    version='0.1',
+    py_modules=['nextaction'],
+    url='https://github.com/nikdoof/NextAction',
+    license='MIT',
+    author='Andrew Williams',
+    author_email='andy@tensixtyone.com',
+    description='A more GTD-like workflow for Todoist. Uses the REST API to add and remove a @next_action label from tasks.',
+    entry_points={
+        "distutils.commands": [
+            "nextaction = nextaction:main",
+            ],
+        }
+)