Move code to package

I moved code to a self-own package. This package is only for GoogleScraper.
But it could not keep backward compatible.
I refered to this site, "Python Project Howto".(http://infinitemonkeycorps.net/docs/pph/) You can move test outside the package if you want.
Package and module name must be different for python interpreter.
So I renamed the GoogleScraper.py to Scraper.py. You can rename again if you want.

I adjusted use.py for new package path.
Now test can be run by 
PYTHONPATH=. python3 -m unittest discover

The ways of installation are the same as #6 which I mention.