1. The bash -x -e command in vagrant/bootstrap.sh didn't work. I had to
remove the -e switch.
2. conf/yarn-site.xml forces YARN to bind to 127.0.0.1. This means that
192.168.0.20:8088/cluster/apps doesn't work. Eliminating the
yarn.resourcemanager.hostname property fixed this.
Once I did that, I still couldn't contact 192.168.0.20 from my host
machine. I suspect there's some configuration that needs to be set (or
removed) to make this work. Given that we don't have any owner for this
code right now, I'm going to remove it.