RFT: pkg_install patches

[Garrett Cooper]

Hi hackers,
    There are a series of patches that I'd like to get reviewed before
jumping onto another project that would clean up and move pkg_install
forward. portmgr has been kind of busy lately (mostly flz), so I don't
think that these have been reviewed by him:

http://www.freebsd.org/cgi/query-pr.cgi?pr=bin/146857 - pkg_create(8):
fix missing error call in uname check added to pkg_version in r206043
http://www.freebsd.org/cgi/query-pr.cgi?pr=bin/146859 - libpkg/msg.c
removal and related cleanup

    I also have some patches outstanding in my p4 workspace that I'd
like to get out into the real world because I added libarchive support
(with bapt, kientzle, and jlaffaye's help) to pkg_install, but I
suppose all in due time (I need to break down things into smaller
chunks for easier consumption).
Thanks!
-Garrett