[scripts] drop ZFS support
Switch back to vesafb, since many people have problems with uvesafb

vesafb seems to work fine with plymouth anyway
Drop video=uvesafb from grub.cfg, wasn't loaded and we have efifb
Drop video=vesafb, not really needed
[scripts] move nvidiabl and ndiswrapper install to scripts/
[scripts] move nvidiabl and broadcom-sta to scripts/
[scripts] arm: execute profiles update outside qemu-user chroot
[molecules] bumblebee is already included in graphic-environment
[scripts] move bumblebee installation to scripts/
Drop HardenedServer, people can just install the sys-kernel/linux-hardened
Drop amd64+x86 images, no longer supported
[molecules] fix syntax in arm-base.common, use %env
[boot] provide the x64 EFI Shell for convenience
[scripts] move shared image setup code to prepare_generic
[scripts] configure mesa through eselect mesa --auto
[scripts] do not hide the output of eselect opengl set
[scripts] set the default sabayon theme if it exists
[molecules] install media-libs/libtxc_dxtn for s3tc support
[scripts] install zfs-kmod
[scripts] iso_build.sh: fix SABAYON_RELEASE handling wrt monthly