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