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

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

fuse: revert kernel_header update.

It seems to be causing problems due to the lack of the new features.

Found by: bapt
Pointed hat: pfg

fuse: revert birthtime support.

The creation time support breaks the data structures used in linux
fuse. libfuse carries it's own header.

Revert the changes for now. We will try to get an agreement with the
fuse upstream maintainers to avoid having to patch the library
headers all the time.

Adjust outsizes:

Recalculate FUSE_COMPAT_ENTRY_OUT_SIZE and COMPAT_ATTR_OUT_SIZE.
These were wrong in the previous commit. They are actually unused
in FreeBSD though.

Pointed out by: Jan Beich

Adjust outsizes:

When birthtime was added (r253331) we missed adding the weight
of the new fields in FUSE_COMPAT_ENTRY_OUT_SIZE and
COMPAT_ATTR_OUT_SIZE. Adjust them accordingly.

Pointed out by: Jan Beich

Update fuse_kernel header.

Bring in the changes from the FUSE kernel interface 7.10
(available under a BSD license).

After 7.10 the linux FUSE developers added support for a
controversial CUSE driver and some linux especific
features that are unlikely to find its way into FreeBSD.

We currently don't implement any of the new features so we
are *not* bumping the FUSE_KERNEL_MINOR_VERSION. The header
should, nevertheless, serve as a template to add the new
features in a compatible manner.

While here adopt some minor cleanups from the upstream version
like removing FUSE_MAJOR and FUSE_MINOR which were never
used. Also add multiple inclusion header guards,

Add creation timestamp (birthtime) support for fuse.

I was keeping this #ifdef'd for reference with the MacFUSE change[1]
but on second thought, this is a FreeBSD-only header so the SVN
history should be enough.

Add missing padding while here.

Reference [1]:
http://code.google.com/p/macfuse/source/detail?spec=svn1686&r=1360

Add creation timestamp (birthtime) support for fuse.

This is based on similar support in MacFUSE.

Import a FreeBSD port of the FUSE Linux module.
This has been developed during 2 summer of code mandates and being revived
by gnn recently.
The functionality in this commit mirrors entirely content of fusefs-kmod
port, which doesn't need to be installed anymore for -CURRENT setups.

In order to get some sparse technical notes, please refer to:
http://lists.freebsd.org/pipermail/freebsd-fs/2012-March/013876.html

or to the project branch:
svn://svn.freebsd.org/base/projects/fuse/

which also contains granular history of changes happened during port
refinements. This commit does not came from the branch reintegration
itself because it seems svn is not behaving properly for this functionaly
at the moment.

Partly Sponsored by: Google, Summer of Code program 2005, 2011
Originally submitted by: ilya, Csaba Henk <csaba-ml AT creo DOT hu >
In collabouration with: pho
Tested by: flo, gnn, Gustau Perez,
Kevin Oberman <rkoberman AT gmail DOT com>
MFC after: 2 months