It was too complicated and Alpine didn't want to cooperate...

Based on FBInk, very minimal but designed to save a (possible) eMMC device brick if in any case that happens eventually. Includes basic functions and UI, interaction is only possible via serial port for security reasons. Utilities will be added soon.

Based on Kobo-Reader repository's one from GitHub.
Changes:
	- U-Boot can now load a second kernel at sector 19456 of the MMC when the Home button is pressed at boot on the Kobo Touch N905C. It boots the default one at sector 2048 otherwise.
	- Miscellanous other changes