[chirp_users] Python3 Update for rpttool?

[Dan Smith]

> Is there a plan to update the rpttool to work with Python3 like the rest of Chirp? I see it hasn't been updated in a while and I am looking to use it with a ID-RP2000V Repeater.

I haven't used that since 2009 when I first wrote it for myself. It's been broken long before python3 even just because it didn't get any love. I was actually thinking I should remove it as I wasn't sure anyone had ever used it. Happy to keep it around if it is useful.

I just did a presumptive conversion just now and will merge it for tomorrow. If you can give it a try, please open a bug with what you get and we can iterate from there (in a bug, not here). If it "just works" please let me know.

--Dan