documentation needs more detail for beginners

[FlorinAndrei]

I'm completely new to the Maestro hardware and software, and I had some trouble making it work on Windows with Python.

I made some changes to the README to guide complete newbies like me:

#9

Thanks!

[FlorinAndrei]

BTW, it seems to work just fine with Python 3.7.4 on Windows, despite the multiple hints that I should use Python 2 instead.