* tests/guix-package-aliases.sh: "guix upgrade foo bar" has always
returned zero; adjust accordingly.
* tests/guix-refresh.sh: "guix refresh -t test idutils" and similar
return zero; adjust accordingly.

Addresses <https://issues.guix.gnu.org/62406>.

With 'set -e', a return status inverted with '!' does not cause the shell to
exit immediately.  Instead use '&& false' to indicate an expected failure.

* tests/guix-archive.sh, tests/guix-build-branch.sh, tests/guix-build.sh,
tests/guix-daemon.sh, tests/guix-download.sh,
tests/guix-environment-container.sh, tests/guix-environment.sh,
tests/guix-gc.sh, tests/guix-git-authenticate.sh, tests/guix-graph.sh,
tests/guix-hash.sh, tests/guix-home.sh, tests/guix-pack-relocatable.sh,
tests/guix-pack.sh, tests/guix-package-aliases.sh, tests/guix-package-net.sh,
tests/guix-package.sh, tests/guix-refresh.sh, tests/guix-shell.sh,
tests/guix-style.sh, tests/guix-system.sh: Replace uses of '! ...' with
'... && false' or `test ! ...` as appropriate.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

With this change, package transformation options used while building a
manifest are saved in the metadata of the manifest entries.

* guix/scripts/build.scm (transformation-procedure): New procedure.
(options->transformation)[applicable]: Use it.  Change to a list of
key/value/proc tuples instead of key/proc pairs.
[package-with-transformation-properties, tagged-object]: New
procedures.  Use them.
(package-transformations, manifest-entry-with-transformations): New
procedures.
* guix/scripts/pack.scm (guix-pack)[with-transformations]: New
procedure.
Use it.
* guix/scripts/package.scm (process-actions)[transform-entry]: Use it.
* tests/guix-package-aliases.sh: Add test.

* tests/guix-archive.sh, tests/guix-build-branch.sh, tests/guix-build.sh,
tests/guix-daemon.sh, tests/guix-download.sh, tests/guix-environment.sh,
tests/guix-gc.sh, tests/guix-git-authenticate.sh, tests/guix-graph.sh,
tests/guix-hash.sh, tests/guix-lint.sh, tests/guix-pack-relocatable.sh,
tests/guix-pack.sh, tests/guix-package-aliases.sh, tests/guix-package-net.sh,
tests/guix-package.sh: Use the shell '!' keyword to negate command exit status
in place of 'if ...; then false; else true; fi'

* tests/guix-package-aliases.sh: Test 'guix show' with multiple packages.

* guix/scripts/package.scm (process-query) <'show>: Remove superseded
packages.
* tests/guix-package-aliases.sh: Add test.

* guix/scripts/show.scm: New file.
* Makefile.am (MODULES): Add it.
* po/guix/POTFILES.in: Add it.
* tests/guix-package-aliases.sh: Add test.
* doc/guix.texi (Invoking guix package): Document it and use it in a example.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

* guix/scripts/search.scm: New file.
* Makefile.am (MODULES): Add it.
* po/guix/POTFILES.in: Add it.
* tests/guix-package-aliases.sh: Add test.
* doc/guix.texi (Invoking guix package): Document it and use it in a
couple of examples.

* guix/scripts/install.scm, guix/scripts/remove.scm,
guix/scripts/upgrade.scm, tests/guix-package-aliases.sh: New files.
* Makefile.am (MODULES, SH_TESTS): Add them.
* po/guix/POTFILES.in: Add them.
* guix/scripts/package.scm (guix-package): Split with...
(guix-package*): ... this.  New procedure.
* doc/guix.texi (Invoking guix package): Document them.
(Binary Installation, Application Setup, Package Management)
(Packages with Multiple Outputs, Package Modules)
(X.509 Certificates, Installing Debugging Files): Use 'guix install' in
simple examples.
* etc/completion/bash/guix (_guix_complete): Handle "install", "remove",
and "upgrade".