refactor(settings): break up the settings into one module per configuration

- moves `config/urls.py` to project_root
- moves  `config/wsgi.py` to project_root
- `config.settings` module is replaced by `config`, selectively applicable
  configs are imported in `config/__init__.py`
- updated comment marker to comply with [PEP-8/inline-comments][1]

[1]: http://legacy.python.org/dev/peps/pep-0008/#inline-comments