Add export option for saved layout sets

Like cck and views have the option to export data and import into another installation, I think composite should allow users to do the same with layout sets.

I many times package up cck and views data into it's own module then use it on multiple sites, to provide a custom made content type. I think it would be great for composite to provide the necessary functionality to import a layout set.

Thanks for reading. If I have any time, not likely this week for sure, I may try to add a patch for it (but please don't count on me). I will post back if I get to start working on it.