Support for python 3.8

[Forest Gregg]

Thanks for a great tool.

Unfortunately, it does not work for python 3.8. I think this might be fixed with by updating the macports version.

terryfy/travis_tools.sh

Line 23 in f8ab4fa

 MACPORTS_VERSION=2.4.1 

[Matthew Brett]

Thanks - I'm giving this a shot over at #21

[Matthew Brett]

I think it's working on current master now - let me know?

[Forest Gregg]

works great, thanks!