Util-linux package, at least as far back as version 2.23.2 as found on
CentOS 7, provides the mkfs.minix and fsck.minix commands. Also blkid
from the same package, recognises minix file systems.
Create version 3 file systems because MINIX 3 [1] is the only supported
version and that reportedly uses version 3 of the file system [2].
[1] MINIX 3 / History
https://en.wikipedia.org/wiki/MINIX_3#History
[2] Regarding MINIX 3 file system
https://groups.google.com/forum/#!topic/minix3/3-TeHR_23X8
"MINIX 3 uses Minix File System (MFS). More precisely MFS V3."
Closes!12 - Add minix file system support