Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

fsirand(8): make WARNS=3 clean

- Drop bogus quad_t cast for di_gen, it is a 32bit type
- Print di_gen with leading zeros, to get consistent output
Before this change, amd64 would print:

ino 18 gen 616ca2bd
ino 19 gen ffffffff95c2a3ff
ino 20 gen 25c3a3d5
ino 21 gen 8dc1472
ino 22 gen 3797056b
ino 23 gen 1d47853a
ino 24 gen ffffffff82d26995

After the change

ino 18 gen 616ca2bd
ino 19 gen 95c2a3ff
ino 20 gen 25c3a3d5
ino 21 gen 08dc1472
ino 22 gen 3797056b
ino 23 gen 1d47853a
ino 24 gen 82d26995

PR: bin/139994 (sort of)
Reviewed by: mckusick

style.Makefile(5):
Use WARNS?= instead of WARNS=.

Default to WARNS=2.
Binary builds that cannot handle this must explicitly set WARNS=0.

Reviewed by: mike

- Backout botched attempt to introduce MANSECT feature.
- MAN[1-9] -> MAN.

Set the default manual section for sbin/ to 8.

Changed MAN to MAN8 so that this builds.

Add generation number randomization. Newly created filesystems wil now
automatically have random generation numbers. The kenel way of handling those
also changed. Further it is advised to run fsirand on all your nfs exported
filesystems. the code is mostly copied from OpenBSD, with the randomization
chanegd to use /dev/urandom
Reviewed by: Garrett
Obtained from: OpenBSD