doc: Update for UEFI systems.

* doc/guix.texi (USB Stick Installation): Mention UEFI.
(Preparing for Installation): Add notes about EFI System Partition, and
mounting partitions before init.
(Proceeding with the Installation): Mention the GRUB-EFI package.
(Using the Configuration System): Lightweight desktop is now a UEFI system.
(GRUB Configuration): Expand on package field. Add indexes.
* gnu/system/examples/lightweight-desktop.tmpl: Adjust to native EFI configuration.

install: Enable SSH in installation image.

* gnu/system/install.scm (%installation-services): Add OPENSSH-SERVICE-TYPE.
* doc/guix.texi (Preparing for Installation)[Networking]: Document it.

maint: The 'release' target builds a VM image.

* gnu/system/examples/vm-image.tmpl: New file.
* Makefile.am (GUIXSD_VM_SYSTEMS, GUIXSD_VM_IMAGE_BASE,
GUIXSD_VM_IMAGE_SIZE): New variables.
(release): Add logic to build a VM image.
(EXAMPLES): Add 'gnu/system/examples/vm-image.tmpl'.
* doc/guix.texi (Running GuixSD in a VM, Installing GuixSD in a VM): Mention the
pre-built VM image.

doc: Update the documentation for the asdf build systems.

* doc/guix.texi (Build Systems): Remove the no-longer relevant parts about
naming inputs.  Add documentation for the new parameters #:asd-system-name and
 #:test-asd-file.

doc: Mention 'sync' after 'dd'.

Suggested by librenoob on #guix.

* doc/guix.texi (USB Stick Installation): Add 'sync' invocation.

doc: Mention 'GUIX_PACKAGE_PATH' in "Defining Packages".

* doc/guix.texi (Defining Packages): Mention 'GUIX_PACKAGE_PATH'.

doc: Document certificate environment variable needed for R.

* doc/guix.texi (X.509 Certificates): Document R as a special case.

services: Add 'thermald-service-type'.

* gnu/services/pm.scm (<thermald-configuration>): New record type.
(thermald-shepherd-service, thermald-service-type): New variables.
* doc/guix.texi (Thermal Management): New section documenting thermald.

system: grub: Expose GRUB's interactive interface settings.

* gnu/system/grub.scm (<grub-configuration>): Add new fields
terminal-outputs, terminal-inputs, serial-unit, and serial-speed.
(grub-setup-io, setup-gfxterm): New procedures.
* doc/guix.texi (GRUB Configuration): Document the new fields.

doc: Suggest a network test command that will definitely be available.

* doc/guix.texi (Running GuixSD in a VM): Suggest the use of `guix
download` to test network connectivity.

doc: Document the branching and rebuild scheduling strategy.

* doc/contributing.texi (Submitting Patches): Document the branching
scheme.

doc: Update "Limitations".

* doc/guix.texi (Limitations): Mention LXDE; increase the package
count; reword sentence about services.

graph: Add Cypher backend.

* guix/graph.scm (%cypher-backend): New variable.
* doc/guix.texi: Add documentation for the Cypher backend of 'guix graph'.

ant-build-system: Allow specifying source directory.

* guix/build-system/ant.scm (ant-build),
guix/build/ant-build-system.scm (default-build.xml): Add parameter
source-dir.
* guix/build/ant-build-system.scm (configure): Pass source-dir on to
default-build.xml.
* doc/guix.texi (Build Systems): Document it.

Co-authored-by: Ricardo Wurmus <rekado@elephly.net>

pull: Honor the standard build options.

Reported by Niall Dooley <dooleyn@gmail.com>
in <https://lists.gnu.org/archive/html/help-guix/2017-05/msg00038.html>.

* guix/scripts/pull.scm (%options): Add --dry-run and all of
%STANDARD-BUILD-OPTIONS.
(show-help): Add call to 'show-build-options-help'.
(%default-options): Add 'system', 'substitutes?', 'graft?',
'max-silent-time', and 'verbosity'.
(guix-pull)[parse-options]: Remove.
Use 'parse-command-line' instead.  Honor --dry-run.

doc: Document (list package output) syntax in operanting-system-packages.

* doc/guix.texi (Globally-Visible Packages): Document (PACKAGE OUTPUT) syntax.

doc: Add references to Emacs-Guix manual.

* doc/htmlxref.cnf: Add links to the real manual.
* doc/contributing.texi (Formatting Code): Add reference to it.
* doc/guix.texi (Package Management): Likewise.

doc: Add 'Debugging Build Failures' node.

* doc/guix.texi (Debugging Build Failures): New node.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

packages: Remove support for PACKAGE-VERSION deprecated syntax.

This syntax had been deprecated since 2016-02-28.

* gnu/packages.scm (%find-package): Remove #:fallback? parameter and handling.
* tests/guix-build.sh: Remove test for "time-1.7" syntax.
* doc/guix.texi (Invoking guix lint): Update 'guix lint' output in example.

refresh: Report packages using the "@" syntax.

* guix/scripts/refresh.scm (list-dependents)[full-name]: New procedure.
Use 'full-name' instead of 'package-full-name'.
* doc/guix.texi (Invoking guix refresh): Adjust example accordingly.