Humps

- Change module structure, use: `from humps.camel import case`
- Add CHANGELOG.md
- Use Twine as setup tool
- Add shell script to build and upload distribution
- You may need to install and configure [Twine](https://github.com/pypa/twine), e.g. use its environment variables
- Extend long package description to match README.rst

- Support conversion of any string to camelCase
- Raise error for non `str` type inputs
- Ignore any non-alphanumeric characters