Merge pull request #37 from srmo/master

[installer][target] setup extraction progress.
[installer] [host] cosmetic
[installer] [target] add .tar.xz support to busybox
[installer] [target] include extractworker on device
[installer] [target] don't extract yet, we have no mkfs
[installer] fix debian packaging
[installer] fix debian packaging again
[installer] [target] don't qDebug() every progress update
[installer] fix debian packaging again again
[installer] [target] fix xz support patch for buildroot
[installer] [target] write log to /mnt on halt; parse network configuration for network installs: write /etc/network/interfaces; /etc/resolv.conf; bring up eth0 with ifup
[installer] [target] make sure system is in utils scope
[installer] [target] fix a couple of issues that only show on QWS
[installer] [target] fix build on target
[installer] [target] hide title bar on QWS target
[installer] [target] add png support and jpeg support to Qt, not as external lib
[installer] [target] fix bad adjustment of windowflags
[installer] [target] centralise target application
[installer] [target] add serial port getty for diagnostics
[installer] [target] if /init dies; kernel panic will occur. Prevent that.