Bring up the minimesos environment frommesos 1.3 (based on JDK7) to a newer version

[scrosby]

Right now, our minimesos integration environment uses mesos 1.3.0 docker images. These are wired to JDK7. Bring our integration environment more up to-date; we don't want to test on a deprecated JDK. Either JDK8 or JDK9.

[DaoWen]

We're using OpenJDK8 to launch Cook in our containerized (docker) testing environment:

https://github.com/twosigma/Cook/blob/master/scheduler/Dockerfile#L16

It's probably important to keep the JDK version in that image up to date with what we expect to use in production; however, I don't think we really care what JDK version is used in the other dependencies' docker images (zookeeper, mesos, etc.) since we just treat them as black boxes.