Use mount --move instead of pivot_root

pivot_root is not supported in initramfs
Disable all nfsd services
initramfs: mount devtmpfs on /dev
grub.cfg: separate menu entries for serial console
grub.cfg: menu entries title improvements
Use upper case hex digits in FAT volume ID

mount UUID=... doesn't work with lower case letters
Mount boot media in initramfs

This will be used for low-memory startup and extra configuration
Support for the low-memory boot mode
rebuild initramfs on uuids change
Kernel command-line handling

Currently the following command-line options are supported:
init, pldnr.debug, pldnr.nomedia, pldnr.modules, pldnr.font,
pldnr.keymap