guix package: Fix indentation of packages to remove.

* guix/scripts/package.scm (show-what-to-remove/install): Add space when
  showing packages to remove.

guix package: 'search-path-environment-variables' traverses module tree once.

* guix/scripts/package.scm (search-path-environment-variables)[manifest-entry->package]:
  Use 'find-best-packages-by-name' instead of 'find-packages-by-name'.
  On a profile with 140 packages, this reduces execution time of this
  procedure from 5.8 seconds to 2.9 seconds (50% improvement.)

guix package: Register non-default profiles as GC roots.

* guix/scripts/package.scm (maybe-register-gc-root): New procedure.
* tests/guix-package.sh (profile): Grep the output of "guix gc
  --list-live" in a couple of places.

Merge branch 'master' into core-updates

guix package: Use the common build options from (guix scripts build).

* guix/scripts/build.scm (%standard-build-options): Change option
  handlers to support multiple seeds.
* guix/scripts/package.scm (show-help): Remove --dry-run, --fallback,
  --no-substitutes, and --max-silent-time.
  (%options): Likewise, and add %STANDARD-BUILD-OPTIONS.
  (%default-options): Add 'verbosity'.
  (guix-package): Call 'set-build-options-from-command-line' instead of
  'set-build-options'.

Merge branch 'master' into core-updates

guix package: Gracefully handle EPIPE on '--search'.

* guix/scripts/package.scm (guix-package): Wrap body of 'search' in
  'leave-on-EPIPE'.

Merge branch 'master' into core-updates

config: '%state-directory' always honors $NIX_STATE_DIR.

* guix/config.scm.in (%state-directory): Honor $NIX_STATE_DIR.
* guix/scripts/package.scm (%profile-directory): Use %state-directory
  directly.
* guix/store.scm (%default-socket-path, log-file): Likewise.

guix package: Gracefully deal with EPIPE on stdout for --list-*.

* guix/scripts/package.scm (leave-on-EPIPE): New macro.
  (guix-package): Use it for 'list-installed', 'list-available', and
  '--list-generations'.
* tests/guix-package.sh: Add test.

Add 'guix archive'.

* guix/scripts/archive.scm, tests/guix-archive.sh: New files.
* Makefile.am (MODULES): Add 'archive.scm'.
  (SH_TESTS): Add 'guix-archive.sh'.
* doc/guix.texi (Invoking guix archive): New section.
* guix/scripts/build.scm: Export 'derivation-from-expression'.
* guix/scripts/package.scm: Export 'specification->package+output'.

Factorize package search between 'guix package' and 'guix build'.

* guix/scripts/package.scm (newest-available-packages): Remove.
  (find-best-packages-by-name): Move to...
* gnu/packages.scm (find-best-packages-by-name): ... here.
  (find-newest-available-packages): Memoize.
* guix/scripts/build.scm (specification->package): New procedure,
  formerly called 'find-package' within 'guix-build'.
  (guix-build): Adjust accordingly.

guix package: allow multiple arguments after -i, -r, and -u.

* guix/scripts/package.scm (%options): Adapt option processors to accept and
  return a second seed value: 'arg-handler', which handles bare arguments (if
  not false).  The install, remove, and upgrade option processors return an
  arg-handler that repeat the same operation.  All other option processors
  return #f as the arg-handler.  Make the arguments to install and remove
  optional.  The upgrade option processor deletes (upgrade . #f) from the
  alist before adding a new entry.
  (guix-package): Procedures passed to 'args-fold*' accept the new seed value
  'arg-handler'.  The 'operand-proc' uses 'arg-handler' (if not false).

* doc/guix.texi (Invoking guix package): Update docs.

* tests/guix-package.sh: Add test.

guix package: Honor the current output when upgrading.

* guix/scripts/package.scm (specification->package+output): Pass OUTPUT
  to 'package-specification->name+version+output'.

Merge branch 'master' into core-updates

Conflicts:
	guix/packages.scm

guix package: Show the output name of what's being removed.

* guix/scripts/package.scm (show-what-to-remove/install): Show the
  output name of packages being removed.

guix package: Fix indentation of "will be removed" messages.

* guix/scripts/package.scm (show-what-to-remove/install): Remove extra
  indentation from the removal sentences.

guix package: Allow removal of a specific package output.

Fixes <http://bugs.gnu.org/15756>.

* guix/profiles.scm (<manifest-pattern>): New record type.
  (remove-manifest-entry): Remove.
  (entry-predicate, manifest-matching-entries): New procedures.
  (manifest-remove): Accept a list of <manifest-pattern>.
  (manifest-installed?): Replace 'name' parameter by 'pattern', a
  <manifest-pattern>.
* guix/scripts/package.scm (options->removable): Return a list of
  <manifest-pattern>.
  (guix-package)[process-action]: Use 'manifest-matching-entries' to
  compute the list of packages to remove.
* tests/profiles.scm: New file.
* Makefile.am (SCM_TESTS): Add it.

guix package: Separate '--remove' option processing.

* guix/scripts/package.scm (options->removable): New procedure.
  (guix-package)[process-actions]: Use it.  Rename 'remove*' to 'remove'
  and 'install*' to 'install'.

ui: Factorize package specification parsing.

* guix/ui.scm (package-specification->name+version+output): New
  procedure.
* guix/scripts/package.scm (specification->package+output): Use it.
* tests/ui.scm ("package-specification->name+version+output"): New test.