extract kernel into debirf, rather than install

[jrollins]

A discussion on this issue got started in ticket #45. The idea is to extract the kernel into the debirf build, rather than install it will apt or aptitude. This will prevent the kernel installation from pulling in it's dependencies, which are just a bootloader and initramfs builder, neither of which are needed in debirf. This will get rid of a couple of extra unneeded packages, as well as stop the creation of a standard initrd in debirf, which was always superfluous.

The one thing pulled in by initramfs-tools that we would most likely like to keep is udev. I will create a new plugin just to install that, which will make it easier to exclude it if it's not desired.

The way to do with is:

debirf_exec dpkg --extract "$KERNEL_PACKAGE" /

for kernel packages from the repo, we can download them with:

debirf_exec aptitude download "$KERNEL_PACKAGE"

[dkg]

just fixing the dpkg --extract command in the description.

[jrollins]

fixed in v0.10