Travis-CI: use JDK 8
Travis-CI: use JDK 8

or-tools/or-tools,google/or-tools,or-tools/or-tools,google/or-tools,google/or-tools,or-tools/or-tools,google/or-tools,or-tools/or-tools,or-tools/or-tools,or-tools/or-tools,google/or-tools,google/or-tools