Re-organise, make importing work from either pyside or pyqt4

[stuaxo]

Hi, This is a bit of a re-org.

• added a setup.py
• moved everything to a package
• made it possible to import the qt or pyside version
• separate the implementation from the qt part + renamed to 'pygletwidget' (in theory it should be possible to add other non QT based backends).
• separated example

It should all work, for uploading to pypi if you follow these instructions http://peterdowns.com/posts/first-time-with-pypi.html

If you're not up for it, I can do this as I'm already setup for this.

I realise you don't care about licenses, but it is a good idea to have one - the best one for not-caring, seems to be the MIT license:

http://choosealicense.com/

https://blog.codinghorror.com/pick-a-license-any-license/