set default packages dir to ~/packages

fixes #22

prefix a makedepends with ! and its treated as a conflict. for example:

makedepends="zlib-dev !gettext"

check if wget is in makedepends.

fixes #11

I think we only need raid1 and maybe raid5 but now we copy the entire md
subdir. so there are room for size optimization here.

use 'make iso' to build the iso image.

This is because we might want to build for usb

This will hopefully fix the checksum errors

install scripts are splitted into separate scripts. The install variable
should contain a list of the scripts. Each script should be the pkgname with
action as suffix. I.E:

install="$pkgname.pre-install $pkgname.post-install"

enable bootchartd to use kernel process accounting for noticing
all processes.

also fix various little bits around the initramfs init.

modifications to makefile and initramfs init that were left out
from previous commit.

include a modified version of bootchartd, and modify the initramfs
to take start recording of boot sequence to /var/log/bootchart.tgz
if "chart" option is specified in boot command line.