Ask for block device, add steps loop, add 'wipe' and 'partition' steps

steps/10-wipe.step

@@ -0,0 +1,12 @@
+#!/bin/sh
+
+echo "~> Going to wipe $blockdevice. You sure? (y/N) "
+read answer
+
+if [ "$answer" == "y" ]; then
+	echo "~> OK. Be patient now, that could take some time..."
+	dd if=/dev/zero of=$blockdevice status=progress
+	return $?
+else
+	exit 1
+fi

steps/20-partition.step

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+echo "~> Setting up $blockdevice with:"
+echo " * 300M EFI (FAT32) partition"
+echo " * <full> crypted (LUKS) root (EXT4) partition"
+
+echo "g\nn\n1\n2048\n+300M\nn\n2\n\n\np\nw"
+
+if [ "$?" -eq 0 ]; then
+	echo "~> Seems to have worked. Yay!"
+	exit 0
+else
+	echo "~> Failed. :("
+	exit 1
+fi