Updated package name to temperusb.

- Update module name to setup.py
- Updated package name and module name in setup.py
- Added additional field to setup.py
- Added README.md to package as long_description

It would probably make sense to change the repository name from temper-python to temperusb to keep things consistent, but this isn't essential. If you do change it, don't forget to update the 'url' value in setup.py.