installer: Offer NM, Connman, and DHCP to non-desktop installs.

* gnu/installer/services.scm (%system-services): Add NetworkManager,
Connman, and the DHCP client.
* gnu/installer/newt/services.scm (run-networking-cbt-page): Add
'network-management?' parameter and honor it.
(run-services-page): Adjust call accordingly.

gnu: Add clp.

* gnu/packages/maths.scm (clp): New variable.

gnu: guitarix: Update to 0.38.0.

* gnu/packages/audio.scm (guitarix): Update to 0.38.0.

gnu: lcms: Fix CVE-2018-16435.

* gnu/packages/ghostscript.scm (lcms)[replacement]: New field.
(lcms/fixed): New variable.
* gnu/packages/patches/lcms-CVE-2018-16435.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.

gnu: libssh2@1.8.0: Move to ssh.scm.

This fixes a top-level circular dependency introduced in
c1f4e6491cecc5d121ef371a8fb2aa0a07030d36.

* gnu/packages/curl.scm (libssh2-1.8.0): Move to...
* gnu/packages/ssh.scm (libssh2-1.8.0): ... here.

services: dropbear: Add default value.

* gnu/services/ssh.scm (dropbear-service-type)[default-value]: New
field.

installer: Add dialog to select networking services.

* gnu/installer/newt/services.scm (run-networking-cbt-page): New procedure.
(run-services-page): Call it.
* gnu/installer/services.scm (%system-services): Add OpenSSH and Tor.
(networking-system-service?): New procedure.
* gnu/installer/steps.scm (format-configuration): Add 'networking' and
'ssh' to the service modules.

installer: Generalize desktop environments to system services.

* gnu/installer/services.scm (<desktop-environment>): Rename to...
(<system-service>): ... this.  Add a 'type' field.
(%desktop-environments): Rename to...
(%system-services): ... this.
(desktop-system-service?): New procedure.
(desktop-environments->configuration): Rename to...
(system-services->configuration): ... this.  Determine the base list of
services based on whether SERVICES contains at least one "desktop"
service.
* gnu/installer/newt/services.scm (run-desktop-environments-cbt-page):
Adjust accordingly.
* gnu/installer.scm (installer-steps): Likewise.

installer: Remove SLiM-specific instructions.

* gnu/installer/newt/services.scm (run-desktop-environments-cbt-page):
Remove "with F1".

installer: Fix wording for "Internet access."

* gnu/installer/newt/network.scm (run-technology-page): Fix wording for
"Internet access."

installer: Use the normalized codeset in the 'locale' field.

* gnu/installer/locale.scm (normalize-codeset): New procedure.
(locale->locale-string): Use it.

installer: Move the 'locale' step before the 'welcome' step.

* gnu/installer.scm (installer-steps): Move the 'locale step before
'welcome.

installer: Simplify locale dialogs.

* gnu/installer/newt/locale.scm (run-language-page): Simplify text.
(run-territory-page): Likewise.
(run-codeset-page): Likewise.
(run-locale-page): Don't call 'run-codeset-page' when "UTF-8" is among
the codesets of LOCALES.

gnu: terminology: Run test suite.

* gnu/packages/enlightenment.scm (terminology)[arguments]: Add
configure-flag to build the test binary.  Use custom 'check phase.  Add
phase to remove test binary.

gnu: terminology: Update to 1.4.0.

* gnu/packages/enlightenment.scm (terminology): Update to 1.4.0.

services: Add 'imap4d-service-type'.

* gnu/services/mail.scm (<imap4d-configuration>): New record type.
(imap4d-shepherd-service): New procedure.
(%default-imap4d-config-file, imap4d-service-type): New variables.
* gnu/services/mail.scm (Mail Services): Document it.

gnu: Add clack.

* gnu/packages/lisp.scm (sbcl-clack, cl-clack): New variables.

Signed-off-by: 宋文武 <iyzsong@member.fsf.org>

gnu: Add ningle.

* gnu/packages/lisp.scm (sbcl-ningle, cl-ningle): New variables.

Signed-off-by: 宋文武 <iyzsong@member.fsf.org>

gnu: Add lack.

* gnu/packages/lisp.scm (sbcl-lack, cl-lack): New variables.

Signed-off-by: 宋文武 <iyzsong@member.fsf.org>

gnu: Add lack-middleware-static.

* gnu/packages/lisp.scm (sbcl-lack-middleware-static)
(cl-lack-middleware-static): New variables.

Signed-off-by: 宋文武 <iyzsong@member.fsf.org>