python: Simple setup.py for helloweb.py

So that it can be installed as egg/scripts via std setuptools machinery.

python/setup.py

+# minimal egg specification for helloweb.py
+from setuptools import setup
+
+setup(
+    name    = 'helloweb',
+    entry_points = { 'console_scripts': ['helloweb = helloweb:main'] },
+
+    # NOTE we can require other eggs via
+    # install_requires = [ ... ]
+)