doc: Encourage signature verification.

* doc/contributing.texi (Submitting Patches): Remind contributors to verify
cryptographic signatures.

daemon: '--listen' can be passed several times, can specify TCP endpoints.

* nix/nix-daemon/guix-daemon.cc (DEFAULT_GUIX_PORT): New macro.
(listen_options): New variable.
(parse_opt): Push back '--listen' options to LISTEN_OPTIONS.
(open_unix_domain_socket, open_inet_socket)
(listening_sockets): New functions.
(main): Use it.  Pass SOCKETS to 'run'.
* nix/nix-daemon/nix-daemon.cc (matchUser): Remove.
(SD_LISTEN_FDS_START): Remove.
(acceptConnection): New function.
(daemonLoop): Rewrite to take a vector of file descriptors, to select(2)
on them, and to call 'acceptConnection'.
(run): Change to take a vector of file descriptors.
* tests/guix-daemon.sh: Add test.

store: Define a default port for TCP connections.

* guix/store.scm (%default-guix-port): New variable.
(connect-to-daemon)[connect]: Use it when (uri-port uri) is #f.
* doc/guix.texi (The Store): Mention the default port number.

gnu: services: use seconds instead of duration strings.

* gnu/services/dns.scm (zone-file, knot-policy-configuration): Use numbers
instead of duration strings.
(verify-knot-policy-configuration): Fix typo.
* doc/guix.texi (DNS Services): Update documentation.

doc: Suggest a QEMU image size large enough for the system examples.

* doc/guix.texi (Installing GuixSD in a Virtual Machine): Increase suggested
image size from 5 GB to 50 GB.

doc: Clarify comment about QEMU qcow2 file sizes.

* doc/guix.texi (Installing GuixSD in a Virtual Machine): Clarify comment about
QEMU's qcow2 virtualized block device file format.

doc: Explain how to use the GCC toolchain.

* doc/guix.texi (Application Setup): Add subsection "The GCC toolchain".

guix: Add texlive importer.

* guix/import/texlive.scm: New file.
* guix/scripts/import/texlive.scm: New file.
* Makefile.am (MODULES): Add them.
* tests/texlive.scm: New file.
* Makefile.am (SCM_TESTS): Add it.
* guix/scripts/import.scm (importers): Add texlive importer.
* doc/guix.texi (Invoking guix import): Document it.

build-system: Add 'texlive-build-system'.

* guix/build-system/texlive.scm: New file.
* guix/build/texlive-build-system.scm: New file.
* Makefile.am (MODULES): Add them.
* doc/guix.texi (Build Systems): Document it.
* gnu/packages/tex.scm (%texlive-tag, %texlive-revision): Remove variables.
(texlife-ref): Remove procedure.

guix package: '--search' sorts by relevance.

* guix/scripts/package.scm (find-packages-by-description): Rewrite to
compute a score based on the number of regexps matched and the number of
matches for each regexp.  Sort according to this score and return it as
a second value.
(process-query) <'search>: Capture the two return values of
'find-packages-by-description'.  Pass #:extra-fields to
'package->recutils'.
* doc/guix.texi (Invoking guix package): Mention relevance, give an
example.

services: rottlog: Make extensible.

* gnu/services/admin.scm (rottlog-service-type)[compose, extend]: New
fields.
* doc/guix.texi (Log Rotation): Mention extension.

services: rottlog: Define <log-rotation> objects.

* gnu/services/admin.scm (<log-rotation>): New record type.
(syslog-rotation-config, simple-rotation-config): Remove.
(%default-rotations): Define as a list of <log-rotation> objects.
(log-rotation->config, log-rotations->/etc-entries): New procedures.
(<rottlog-configuration>)[periodic-rotations]: Remove.
[rotations]: New field.
(rottlog-etc): Use 'log-rotations->/etc-entries'.
* doc/guix.texi (Log Rotation): Update accordingly.

packages: Add 'specifications->manifest'.

* gnu/packages.scm (specifications->manifest): New procedure.
* doc/guix.texi (Invoking guix package): Change example from using
'(compose list specification->package+output)' to using
'specifications->manifest'.

doc: Add Hartmut to the @copying section.

* doc/guix.texi: Add a copyright line for Hartmut.

doc: Add missing node in master menu.

* doc/guix.texi (Top): Add missing ref to "Debugging Build Failures".

doc: Adapt to multiple bootloader support.

* doc/guix.texi (GRUB configuration): Rename to "Bootloader
  configuration".
  Remove device-mount-point field from menu-entry description.
  Adapt occurences of "GRUB" in other sections.

doc: Use 'guix environment --no-grafts' to debug build failures.

* doc/guix.texi (Debugging Build Failures): Pass --no-grafts to 'guix
environment' and explain.

services: guix: Add 'max-silent-time' and 'timeout'.

* gnu/services/base.scm (<guix-configuration>)[max-silent-time]
[timeout]: New fields.
(guix-shepherd-service): Honor them.
* doc/guix.texi (Base Services): Document them.

scripts: refresh: Add -m manifest option.

* guix/scripts/refresh.scm (%options): Add -m option,
(show-help): document it,
(packages-from-manifest): new procedure,
(guix-refresh): use packages from manifest if specified, otherwise
keep the previous behaviour.
* doc/guix.texi (Invoking guix refresh): document new option.

daemon: Add '--timeout' and '--max-silent-time'.

* nix/nix-daemon/guix-daemon.cc (GUIX_OPT_TIMEOUT)
(GUIX_OPT_MAX_SILENT_TIME): New macros.
* nix/nix-daemon/guix-daemon.cc (options): Add '--timeout' and
'--max-silent-time'.
(parse_opt): Honor them.
* tests/guix-daemon.sh: Add test.
* doc/guix.texi (Invoking guix-daemon): Document the options.
(Common Build Options): Properly describe default
timeout/max-silent-time value.  Add cross-ref to "Invoking
guix-daemon".