Fix demos on Travis [demos]
Fix demos on Travis [demos]


Former-commit-id: 0c7ef1f7cf1107030edd7dc2a0747ce6f3477292 [formerly d2559b0cd1f9dcc867abc21c032ba75899ac4f6f]
Former-commit-id: 0eb14c0607be4b4117fbfd93d6d0ad58487f34f0
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine