Default compresssion format in pkgsrc & extensions

[David Brownlee <abs%absd.org@localhost>]

        Two questions here:

        First, can we pick a standardised extension for binary packages
        which does not change whether the file is gzipped or bzipped?
        Something like .tpz? Exposing the compression format in the file
        extension is just confusing for no real benefit. It makes mixing
        packages with different formats problematic, and as a user of
        bzipped packages I've been bitten a few times when pkg_add has
        tried to look for a .tgz package as a remote dependency (though
        that may have been fixed now)

        As an additional benefit we can drop the .t[gb]z wildcard in
        pkg_add's remote ftp lookup which breaks on many ftp servers.


        Additionally - iff the above is done, does it make sense to
        adjust the default compression format on at least some platforms,
        potentially leaving it as gzip on slower/lesser memory OS/Arch
        combinations.

        Its a pit we can't use some higher compression format such as
        7zip's LZMA - some package sizes in gzip, bzip2 and 7z below

           15643934 firefox3-3.0.10.tgz
           13675766 firefox3-3.0.10.tbz
           10376442 firefox3-3.0.10.7z

          142738351 openoffice3-3.0.1nb4.tgz
          132794840 openoffice3-3.0.1nb4.tbz
           89951335 openoffice3-3.0.1nb4.7z

              65645 p5-XML-Simple-2.18nb1.tgz
              47085 p5-XML-Simple-2.18nb1.tbz
              43944 p5-XML-Simple-2.18nb1.7z