Add PyPy3 to Travis
Add PyPy3 to Travis

landonb/argcomplete,kislyuk/argcomplete,kislyuk/argcomplete,lisongmin/argcomplete,neizod/argcomplete,douglas-larocca/argcomplete,landonb/argcomplete,neizod/argcomplete,douglas-larocca/argcomplete,lisongmin/argcomplete