Doc updates, refactor code layout, python package

setup.py

@@ -0,0 +1,20 @@
+from setuptools import setup, find_packages
+
+setup(
+    name="betterproto",
+    version="1.0",
+    description="A better Protobuf / gRPC generator & library",
+    url="http://github.com/danielgtaylor/python-betterproto",
+    author="Daniel G. Taylor",
+    author_email="danielgtaylor@gmail.com",
+    license="MIT",
+    entry_points={
+        "console_scripts": ["protoc-gen-python_betterproto=betterproto.plugin:main"]
+    },
+    packages=find_packages(
+        exclude=["tests", "*.tests", "*.tests.*", "output", "output.*"]
+    ),
+    package_data={"betterproto": ["py.typed", "templates"]},
+    install_requires=["grpclib", "protobuf"],
+    zip_safe=False,
+)