Improved partition detection, don't rely on gdisk to detect EFI System Partition (as it can potentially hang until the user presses Enter in the terminal...#cough)

Don't hang when formating ext partitions (Upstream changed the behaviour of mkfs.ext2|3|4. It now asks for a confirmation unless -F is used.)

 - Don't crash when blkid returns empty model info
 - Don't crash when blkid returns size unit "K" instead of "k"
 - Ignore malformed blkid output or device info we can't parse
 - Ignore /dev/fd0

Fixed slideshow, updated slideshow content, removed unused l10n slideshow and its package definition

Fixup: remove duplicate function introduced in 7db799a3

Remove dead timezone code (removed in cff429d4, readded e6a8032d)