Port to python3

[loupianche]

Python2 will be removed soon from distributions.

[versusvoid]

Wayland tool using python 2.
Really?

[mhsabbagh]

If I am to work on this I won't start until mid of June (I am busy at the moment). I have nothing against it; Any pull request porting the program to Python 3 is welcome (Just make sure you also change the dependencies accordingly).

@versusvoid There's nothing inhernetly in Wayland that says you should use Python 2 or 3, or C or C++ or RottenTomatoes' user reviews as your language. If you would like to submit a patch I would be happy to accept.