Reverted USRSTACK definition in machine/vmparam.h: needed
for /usr/bin/gcore utility.
Format of fs superblock updated from OpenBSD 5.6.
Fsck utility modified.
Libc: added routines strlcat, strlcpy.
Include file sys/queue updated from OpenBSD.
Fsck utility ported from OpenBSD.
Fixed ufstool and fsck compatibility.