Remove extra white space at EOL

Signed-off-by: Maxime Hadjinlian <maxime.hadjinlian@devialet.com>
Add setup.py

Add an installer, to install grabserial, simply do:
python setup.py install

This could help to put this into Pypi, or to create a Debian packages.

Signed-off-by: Maxime Hadjinlian <maxime.hadjinlian@devialet.com>