travis: use JDK 8 to unbreak dynamodb-local (#825)
travis: use JDK 8 to unbreak dynamodb-local (#825)

* add Python 3.8

* downgrade to jdk8

* Update .travis.yml

* Update .travis.yml

* Update .travis.yml

* Update .travis.yml
jlafon/PynamoDB,pynamodb/PynamoDB