we create /boot, swap and / by default
using -r will create raid1 devices with a single disk.

fixes http://redmine.alpinelinux.org/issues/show/94

Package no longer exist

we mignt want boot from usb disks in raid for example...

and strip trailing / from mounted partition

nangel helped me with this one

will install the running system on given disk.
So far it can only use *all* disk.