Replace libexecdir with datadir

According to the FHS.  Testing scripts and examples which are all
architecture independent should be installed in a subdirectory
under /usr/share.

  http://www.pathname.com/fhs/2.2/fhs-4.11.html

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Fix zfs_config.h install permissions

The default permissions used by install are 755.  Since this
file isn't executable 644 is more appropriate.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Add KMODDIR to install target

Provide a mechanism to control the directory name the modules
are installed in.  The kernel privdes INSTALL_MOD_DIR for
this but it was hardcoded to be 'addon/zfs'.

Add a KMODDIR variable which can be passed to 'make install'
to override the default directory name.  While we're here
change the default from 'addon/zfs' to 'extra' which is the
kernel.org default.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Add --with-dracutdir configure option

The standard dracut directory has moved from /usr/share/dracut to
/usr/lib/dracut.  To ensure the dracut modules get installed in
the correct location provide a --with-dracutdir configure option
to set the path.

The default install location has been updated to /usr/lib/dracut
which is used by more current versions of Fedora.  However, this
default is overriden by the RPM packaging for consistency.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Remove ARCH packaging

The kernel modules are now available in the Arch User Repository
(AUR) via zfs.  Since their packaging is maintained and superior
to ours it is being removed from the tree.

  https://wiki.archlinux.org/index.php/ZFS

Now that various distributions are picking up the packages we
should eventually be able to remove most of this infrastructure.
Packaging belongs with the distributions not upstream.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Retire ZFS.RELEASE file

The ZFS.RELEASE file was originally added to document which
version of OpenSolaris the ZoL code was based on.  However,
that's no longer particularly important or useful.  We'll
likely never see a new onnv_* drop from Solaris, and even
if we do the ZoL changes are now extensive enough they
could not be easily applied.  We now treat Illumos as the
official upstream and cherry pick the patches we need.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Refresh links to web site

A few files still refer to @behlendorf's private fork on
github.  Use the primary web site URL instead.  Two typos
are also corrected.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Fix zdb.8 macro warning

Detected by rpmlint the 'rpool/export/home' section was being
interpretted by troff as an undefined macro.  This resulted
in the 'rpool/export/home' output being omitted from 'man zdb'.

This was caused by starting the line with a ' character.  By
moving the 'in' down to the next line we're able to fix it.

  zfs.x86_64: W: manual-page-warning /usr/share/man/man8/zdb.8.gz
  450: warning: macro `rpool/export/home'' not defined

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>