fixes CC-177, add default timeouts to health checks

This adds support for killing health checks after some period of time. Processes as now spawned in a process group and the entire process group is killed together. Killing the process group with -PID does not work as expected within a docker container so the pids are enumerated. It also adds zombie reaping to the container controller (pid 1).

Some dead code is also removed and the logs retried for failed container runs now uses --tail.