* Update gdk-pixbuf to 2.28.0
* Update build to the latest standards
* Move plugins to /usr/lib/plugins

	deleted:    libs_toolkit/gdk_pixbuf/gdk-pixbuf-2.26.5-cachelocation.patch.xz
	deleted:    libs_toolkit/gdk_pixbuf/gdk-pixbuf-2.26.5-slackware.patch.xz
	new file:   libs_toolkit/gdk_pixbuf/gdk-pixbuf-2.28.0-cachedir.patch.xz
	modified:   libs_toolkit/gdk_pixbuf/gdk_pixbuf.build