testing/nvramtool and testing/coreboot-configurator: new aports

https://review.coreboot.org/coreboot nvramtool manipulates nvram from userspace.

https://github.com/StarLabsLtd/coreboot-configurator A simple GUI to change settings in coreboot's CBFS, via the nvramtool utility. It is especially useful on Star Labs laptops but is usable on any computer with coreboot.

coreboot-configurator depends on nvramtool to function, but can open without it. Not adding nvramtool as a dependency is intentional since nvramtool can be provided by the user if desired.