Fixed .travis.yml [skip CI]
Fixed .travis.yml [skip CI]


Former-commit-id: 79e3bbec25468c9115a4848c8569c9ac981cda7a [formerly 31f467ddb23e98fbb1bc977af0928fe1ba69c8b6]
Former-commit-id: 3e8c72517d663b332a6c8a44872ba1500a4846c9
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine