Refactored to use topics support in natty

I should have noted that we still have access to this in the papertrail log, just not at ERROR level.  The Java app logs debug from flashlight at INFO level (what can I say, I like to keep it confusing :) ).  Our Go-side logging also supports trace level logging, which is enabled by setting the environment variable TRACE=true.

I've been using debug level for stuff that on the Java side might be INFO or WARN, i.e. stuff that's useful to provide context to what's happening in the application.  I reserve trace level for stuff that traces the flow of data/logic at a fairly fine-grained level (e.g. method X called with args Y, Z).