Improve logging for Samza

Often Samza jobs keep running for days (and in our case months). Often log messages generated by the job get rolled over. A lot of information that is critical for debugging a job (like the jmx server port, URL, job model for the current container, configuration that was passed to the container) is often printed when the job starts. However, since logs get rolled over (by Yarn/ by sys-administrators) when they exceed a certain size, this information is lost.

This JIRA is to add a separate samza-container-$containerID-startup.log file with each container. This will have information useful for debugging the job.