Move the libraries into separate packages

From day one the various ZFS libraries should have been placed in their
own sub-packages.  Primarily this allows for multiple major versions of
the libraries to be concurrently installed.  It also facilitates a
smaller build environment by minimizing the required dependencies.

The specific changes required to split the libraries from the utilities
are as follows:

* libzpool2, libnvpair1, libuutil1, and libzfs2 packages were added
  and contain the versioned shared libraries.  The Fedora packaging
  guidelines discourage providing static libraries so they are not
  included in the packages.

  http://fedoraproject.org/wiki/Packaging:Guidelines#Packaging_Static_Libraries

* The zfs-devel package was renamed libzfs2-devel and the new package
  obsoletes the old zfs-devel package.   This package includes all
  the required headers for the libzpool2, libnvpair1, libuutil1, and
  libzfs2 libraries and their respective unversioned shared libraries.

  This package should eventually be split in to individual lib*-devel
  packages but it will still take some work to cleanly separate them.
  Therefore the libzfs2-devel package provides the expected lib*-devel
  packages so the all proper dependencies can still be created.

  http://fedoraproject.org/wiki/Packaging:Guidelines#Devel_Packages

* Moved '/sbin/ldconfig' execution from the zfs packge to each of the
  new library packages as described by the packaging guidelines.

  http://fedoraproject.org/wiki/Packaging:Guidelines#Shared_Libraries

* The /usr/share/doc/ files were moved in to the libzfs2-devel package.

* Updated config/deb.am to be aware of the packaging changes.  This
  ensures that 'deb-utils' make target converts all the resulting
  packages generated by the 'rpm-utils' target.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes: #2329
Closes: #2341
Issue: #2145