gnu: itstool: Add python2-libxml2 to propagated-inputs.

This is a followup to commit 7ce3224247d3acd559841f23d1b4b49d073b15f5.

* gnu/packages/glib.scm (itstool)[propagated-inputs]: Add python2-libxml2.

Merge branch 'master' into core-updates

Merge branch 'master' into gtk-rebuild

gnu: dbus-glib: Propagate inputs dbus and glib.

* gnu/packages/glib.scm (dbus-glib): Propagate inputs dbus and glib.
* gnu/packages/audio.scm (patchage),
  gnu/packages/gnuzilla.scm (icecat),
  gnu/packages/python.scm (python-dbus): Drop inputs dbus and glib.
* gnu/packages/gnome.scm (colord, gconf, gnome-vfs, upower),
  gnu/packages/mail.scm (claws-mail),
  gnu/packages/messaging.scm (hexchat),
  gnu/packages/wicd.scm (wicd): Drop input dbus.

Merge branch 'master' into gtk-rebuild

Conflicts:
	gnu/packages/gtk.scm

Merge branch 'master' into core-updates.

Merge branch 'wip-glib' into master.

Conflicts:
	gnu/packages/package-management.scm

Remove all the 'CC=gcc' hacks for 'g-ir-scanner'.

* gnu/packages/glib.scm (telepathy-glib)[arguments]: Remove.
* gnu/packages/gtk.scm (at-spi2-core, gtk+-2): Remove #:make-flags.
* gnu/packages/gnome.scm (libpeas, librsvg, vala, vte, json-glib,
  libxklavier, libsoup, libsecret, colord, geocode-glib, libgweather):
  Remove #:make-flags or the '(setenv "CC" "gcc")' phase.

gnu: python-pygobject: Update to 3.16.1.

* gnu/packages/glib.scm (python-pygobject): Update to 3.16.1.

gnu: glibmm: Update to 2.44.0.

* gnu/packages/glib.scm (glibmm): Update to 2.44.0.

gnu: libsigc++: Update to 2.4.1.

* gnu/packages/glib.scm (libsigc++): Update to 2.4.1.

gnu: dbus-glib: Update to 0.104.

* gnu/packages/glib.scm (dbus-glib): Update to 0.104.

gnu: itstool: Update to 2.0.2.

* gnu/packages/glib.scm (itstool): Update to 2.0.2.

gnu: gobject-introspection: Update to 1.44.0.

* gnu/packages/glib.scm (gobject-introspection): Update to 1.44.0.
  [source]: Use mirror://gnome.
  [arguments]<#:phases>: Remove.
* gnu/packages/patches/gobject-introspection-cc.patch: Rewrite to
  set os.environ['CC'] in 'giscanner/__init__.py'.

Merge branch 'core-updates'

gnu: glib: Move html documentation to $doc/share/gtk-doc/html.

* gnu/packages/glib.scm (glib)[arguments]<#:configure-flags>:
  Pass "--with-html-dir=$doc/share/gtk-doc/html".

gnu: dbus: Update to 1.8.16.

* gnu/packages/glib.scm (dbus): Update to 1.8.16.

gnu: glib: Add search path specification for 'GIO_EXTRA_MODULES'.

* gnu/packages/glib.scm (glib): Add specification for 'GIO_EXTRA_MODULES'.

gnu: glib: Update to 2.44.0.

* gnu/packages/glib.scm (glib): Update to 2.44.0.

Merge branch 'master' into core-updates