getwindowsversion().major doesn't work with Python 2.6

[Jamesc359]

Using named tuples needlessly breaks compatibility with versions of python <= 2.6

Changing line 313 from:
if sys.platform == 'win32' and sys.getwindowsversion().major >= 5:

To:
if sys.platform == 'win32' and sys.getwindowsversion()[0] >= 5:

fixes the issue.

youtube-dl --version
2012.02.27
python --version
Python 2.6.1
Windows Vista 64Bit