The previous pipeline model required a lot of setup and abstracted away
the processing of records. By passing a HandlerFunc to the consumer we
keep the business logic of processing of records closer to the use of
the consumer.
* Add refactoring note and SHA to README
Requiring the Logger be passed in to each of the structs was causing
Panics if the Logger was omitted.
* Add function for overriding the default logger
* Remove panics caused by initialization
To allow for different logging endpoints we'll introduce a Logger
interface that will be passed into the pipeline during initialization.
* Add Logger interface
* Use logger interface in pipeline and emitters
