Remove Zookeeper per-test fixture
Remove Zookeeper per-test fixture

Rather than run a zookeeper server for each test, use a single
server that we already expect to be running, and rely on the chroot
to ensure that tests don't collide.  This is similar to how we
treat databases.

Change-Id: Ib1ec7fee601a26ab2b3275b99c34d89365dbf064

Tesora/tesora-nodepool,Tesora/tesora-nodepool