add release names ("squeeze", etc) to list of releases to choose from
move default values to separate file to get rid of warnings
use a list of mirrors that will work for both Debian and Ubuntu
support selecting the 'arch' to install, currently armhf and armel
clean up install_activity and create a landscape view
run dpkg in noninteractive mode to get rid of warning messages
run final setup stage in the Debian chroot (closes #49)

The tar warning was caused by the busybox tar still being in the path,
and its much more limited than the GNU tar in Debian.
standardize name of "Image Path" variable names to: image_path
rename misnamed defaults.key to proper defaults.xml
convert NativeHelper.args to a method so its current when its used

if image_path is a preference, it could change at any time.
make "Image Path" a preference rather than staticly set to /sdcard/debian.img
make app_bin unpacking run as normal user, no need to run as root
bump version to v0.4.2 build 7