Use the ext4 file system for SLE12 nodes (default is btrfs)
Merge pull request #346 from jsuchome/use-ext-filesystem-for-sle12x

Use the same file system for SLE12 nodes as for SLE11SP3
handle multiple NTP servers (bnc#895824)

sntp seems to use only the first NTP server and ignore others,
so we iterate over the list and stop waiting when we find a working one
https://bugzilla.novell.com/show_bug.cgi?id=895824