pack: Add "none" compressor.

* guix/scripts/pack.scm (%compressors): Add compressor "none"; prepend
extension with ".".
(self-contained-tarball, docker-image): Assume compressor extensions start
with period.
* doc/guix.texi (Invoking guix pack): Document it.

1 files changed, 1 insertions, 1 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index 816064383c..bff0788b2f 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -2630,7 +2630,7 @@ configuration triplets,, autoconf, Autoconf}).
 @item --compression=@var{tool}
 @itemx -C @var{tool}
 Compress the resulting tarball using @var{tool}---one of @code{gzip},
-@code{bzip2}, @code{xz}, or @code{lzip}.
+@code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
 
 @item --symlink=@var{spec}
 @itemx -S @var{spec}