services: cuirass: Add fallback parameter.

* gnu/services/cuirass.scm (<cuirass-configuration>)[fallback?]: New field.
(cuirass-shepherd-service): Take it into account.
* doc/guix.texi (Continuous Integration): Document it.

services: sysctl: Fix typo.

* gnu/services/sysctl.scm: Fix typo of 'make-sysctl-configuration'.

services: elogind: Start from the Shepherd.

Fixes <http://bugs.gnu.org/27580>.
Reported by William <w@vieta.uk>.

* gnu/services/desktop.scm (elogind-shepherd-service): New procedure.
(elogind-service-type): Extend SHEPHERD-ROOT-SERVICE-TYPE.

services: dbus, polkit: Add default value.

* gnu/services/dbus.scm (dbus-root-service-type)[default-value]: New
field.
(polkit-service-type)[default-value]: New field.

services: Add 'sysctl-service-type'.

* gnu/services/sysctl.scm: New file.
* doc/guix.texi (Miscellaneous Services): Document it.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.

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.

services: network-manager: Specify a default value.

* gnu/services/networking.scm (network-manager-service-type)[default-value]:
New field.

services: cuirass: Extend rottlog with log rotations.

* gnu/services/cuirass.scm (cuirass-log-rotations): New procedure.
(cuirass-service-type): Use it to extend ROTTLOG-SERVICE-TYPE.

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.

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.

Merge branch 'master' into staging

gnu: Add knot-service-type.

* gnu/services/dns.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
* doc/guix.texi (DNS Services): New subsubsection.

Merge branch 'master' into staging

services: openssh: Don't depend on networking.

* gnu/services/ssh.scm (openssh-shepherd-service): Drop requirement.

services: openssh: Don't depend on networking.

* gnu/services/ssh.scm (openssh-shepherd-service): Drop requirement.

services: guix: Authorize the key for bayfront.guixsd.org.

* gnu/services/base.scm (%default-authorized-guix-keys): Add
"bayfront.guixsd.org".

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.

Merge branch 'master' into staging

services: nscd: Adjust activation snippet for /etc/resolv.conf symlinks.

Fixes <http://bugs.gnu.org/26809>.
Reported by Mark H Weaver <mhw@netris.org>.

* gnu/services/base.scm (nscd-activation): Use 'lstat' instead of
'file-exists?'.