CDK-604: Added commands to generate logging and Flume configs

* The Flume configuration defaults to an AvroSource listening on 0.0.0.0:41415
* The Flume configuration defaults to a file channel
* The log4j configuration defaults to writing to port 41415, but requires the hostname
* The log4j configuration requires a package or class name to log to Flume, or a
  switch of --log-all to configure the rootLogger.
* Besides the unit tests, I ran some manual tests on a cluster by completing the
  logging example, but using the tool derived configs rather than the ones that
  shipped with the example.
I think that the *defaults* are for demo purposes because we aren't going to be able to create defaults that you could put in production. So the question is: what is the best way to use this to prepare users so that their path to production is as easy as it can be?

I think that is by creating files that can easily be edited. The help on this command can't explain these options in detail, but correct properties with good comments could. In addition, the Flume user guide is in terms of the configuration options, not the switches that this will use. I think that the work-flow for getting a working config to production will be creating a config and then editing it, rather than adding a switch to the command and recreating it. There's more opportunity to learn about the options that way.