Add a Dockerfile.

Thanks progrium for logspout
Add a Makefile.

Thanks progrium for logspout
Annotate published ports in Dockerfile.
Add build directory to gitignore.
Be terser.
Parameterize Makefile.
Use the local input and output packages.
Switch from log4go to stdlib log package.
Begin converting KafkaProducer into a service object.
Extract Sarama configuration to helper functions.
Reorder Dockerfile for efficiency.
Empty sarama.Producer.Errors() channel to keep things flowing.
Move KafkaProducer startup out to main().
Fix bug with ServeStatistics when parse=false.
Add KafkaProducer activity statistics.