Update to Python 3

[hellocatfood]

Since January 1st 2020 Python 2 reached end of life and newer versions of some distributions no longer ship it. gimp-python relies on python2 and is not in the repositories of some distributions (such as Ubuntu) which means this plugin no longer works (unless manually compiled).

To ensure it works with future versions of Gimp the plugin will need to be updated to Python 3