Revert "add new python versions to travis.yml"
Revert "add new python versions to travis.yml"

This reverts commit 6f799008e1cd66063b8fde5d898f07eea23b7689.

yungchin/pykafka,wikimedia/operations-debs-python-pykafka,benauthor/pykafka,benauthor/pykafka,benauthor/pykafka,wikimedia/operations-debs-python-pykafka,thedrow/samsa,yungchin/pykafka,wikimedia/operations-debs-python-pykafka,thedrow/samsa,thedrow/samsa