Use Python 3.x syntax

First step towards Python 3.x support.
Merge pull request #3 from yegorich/py2to3

Use Python 3.x syntax
Option to exit program based on string match.
Merge pull request #4 from simeonmiteff/master

Option to exit program based on string match.
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>
Merge pull request #5 from maximeh/master

Add setup.py and clean extra whitespace