Mbst 9820 youview initial output

 - Refactor of logic around which elements are output for a given piece of content
 - Improved testing
 - Refactor of flags to allow enabling of test endpoints separately from upload feed tasks for each publisher's upload
 - Initial version of transaction store - stores content ids against transaction id per publisher, and has a placeholder for a transaction status
 - Initial version of an BroadcastEventGenerator, with hardcoded fields where values are unknown/not yet ingested from NITRO 
That's true... that may well work. This is mostly to try and abstract out the common logic that cropped up with three *GenreMapping classes. The Nitro one is very much a placeholder for now, it's not apparent at this stage whether it will work in the same manner as the others, so I'm holding off extensive refactoring of this code at this stage. Will keep this idea in mind though, ta.