utils: 'current-source-directory' is now purely an expansion-time thing.

* guix/utils.scm (extract-directory): Remove.
(current-source-directory): Rewrite as a 'syntax-case' macro.

doc: Recommend against marketing phrases in descriptions.

* doc/guix.texi (Synopses and Descriptions): Add note about marketing
phrases.

gnu: lxqt-common: Add missing inputs.

* gnu/packages/lxqt.scm (lxqt-common)[inputs]: Add qtbase,
qttools, qtx11extras.

gnu: lxqt-session: Add missing inputs.

* gnu/packages/lxqt.scm (lxqt-session)[inputs]: Add qtbase,
qttools, qtx11extras.

gnu: liblxqt: Add missing inputs.

* gnu/packages/lxqt.scm (liblxqt)[inputs]: Add qtbase,
qttools, qtx11extras.

gnu: libqtxdg: Build with qtbase.

* gnu/packages/lxqt.scm (libqtxdg)[propagated-inputs]: Remove qt.
[inputs]: Add qtbase.

gnu: lxqt: Update uris.

* gnu/packages/lxqt.scm (libqtxdg, liblxqt, lxqt-common,
lxqt-session)[source]: Project tarballs have been replaced with Github
archive tarballs.

gnu: starman: Update to 0.4014.

* gnu/packages/web.scm (starman): Update to 0.4014.

gnu: calibre: Build with qtbase.

* gnu/packages/ebook.scm (calibre)[inputs]: Remove qt, add qtbase.
[native-inputs]: Remove qt, add qtbase.

gnu: avidemux: Build with modular qt.

* gnu/packages/video.scm (avidemux)[inputs]: Remove qt, add qtbase, qttools.

gnu: avidemux: Use 'modify-phases'.

* gnu/packages/video.scm (avidemux)[arguments]: Use 'modify-phases'.

gnu: avidemux: Add hardware acceleration support.

* gnu/packages/video.scm (avidemux)[inputs]: Add libva, libvdpau.

gnu: libressl: Update to 2.3.6.

* gnu/packages/tls.scm (libressl): Update to 2.3.6.

gnu: openntpd: Update to 6.0p1.

* gnu/packages/ntp.scm (openntpd): Update to 6.0p1.

gnu: scribus: Build with modular qt.

* gnu/packages/scribus.scm (scribus)[inputs]: Remove qt, add qtbase,
qtdeclarative, qttools.

gnu: alsa-modular-synth: Build with modular qt.

* gnu/packages/audio.scm (alsa-modular-synth)[inputs]: Remove qt,
add qtbase, qttools.

gnu: drumstick: Build with modular qt.

* gnu/packages/music.scm (drumstick)[inputs]: Remove qt, add qtbase, qtsvg.

gnu: vmpk: Build with modular qt.

* gnu/packages/music.scm (vmpk)[inputs]: Remove qt, add qtbase, qtsvg,
qttools, qtx11extras.

gnu: synthv1: Build with modular qt.

* gnu/packages/music.scm (synthv1)[inputs]: Remove qt, add qtbase, qttools.

gnu: powertabeditor: Build with qtbase.

* gnu/packages/music.scm (powertabeditor)[inputs]: Remove qt, add qtbase.