Using __getattr__ for nicer configuration API

Typically, you'll read configuration from files (such as YAML) and get them as a dictionary. However in Python you'd like to write config.httpd.port and not config['httpd']['port']

__getattr__ is a hook method that's called by Python when regular attribute lookup fails (not to be confused with the lower level __getattribute__, which is much harder to work with). You can use it to wrap the configuration dictionary. Here's a small example.