- changed grub2 early boot script to search for the fs-uuid
  of the boot filesystem in order to locate the config file
- removed unneeded/wrong message
- don't show the same message twice
- netboot: fixed setup of swap device in $imageSwapDevice
  If the partition table stays untouched the variable
  was not set which caused a broken fstab entry for
  swap. This patch makes sure the swap device variable
  is set in any case