ST3 support

I have ported the py files (to work in both python 2 and 3). Since ST3 requires python3 files, however this may not be enough for it to work on ST3...

*I can't get it connecting to my git on my system (running on Ubuntu). However, this could be separate issue (i.e. I haven't set it up correctly) as I've never tried using this with ST2...*