* Add config.h and rules.mk support for data driven keymaps
* tidy up after rebase
* Rename key as it can contain more than just keyboard overrides
* tidy up after rebase
* Add validation
* Allow <keyboard>.h to be optional when going data driven
* Remove stub files as no longer required
* Rename function
* Remove include of layouts.h for now
* Take advantage of type=keyboard_folder
* Take advantage of type=keyboard_folder - kb should still be mandatory