Plugins would require an API to build on top and this is not something we have any plans for currently. Should it make it in eventually it will be relatively far out in the future I'm afraid.

kingzeus - Json is pretty easy to parse and it wouldn't be hard to write a command line utility to read in a Json file and write out a custom format. I know it's a bit more painful then having plugin support, but I'd much rather have all the other features first