Install mesh UI desktop background

Makefile

 	mkdir -p ${DESTDIR}${PREFIX}/bin
 	mkdir -p ${DESTDIR}/etc/${APP}
 	cp -r image_build/* ${DESTDIR}/etc/${APP}
+	install -m 755 img/backgrounds/${APP}_mesh_background.png ${DESTDIR}${PREFIX}/share
 	install -m 755 src/* ${DESTDIR}${PREFIX}/bin
 	install -m 755 src/${APP}-meshweb ${DESTDIR}${PREFIX}/bin/meshweb
 	install -m 755 src/${APP}-controlpanel ${DESTDIR}${PREFIX}/bin/control
 	install -m 644 man/${APP}-restore-local.1.gz ${DESTDIR}${PREFIX}/share/man/man1/restore.1.gz
 	bash -c "./translate install"
 uninstall:
+	rm -f ${PREFIX}/share/${APP}_mesh_background.png
 	rm -f ${PREFIX}/share/man/man1/backup.1.gz
 	rm -f ${PREFIX}/share/man/man1/restore.1.gz
 	rm -f ${PREFIX}/share/man/man1/${APP}*.1.gz

src/freedombone-image-customise

 # Whether to install non-free wifi drivers for the mesh client
 INSECURE='no'
 
+# optional desktop background image for mesh
+MESH_DESKTOP_BACKGROUND_IMAGE=/usr/local/share/${PROJECT_NAME}_mesh_background.png
+
 enable_eatmydata_override() {
 	chroot $rootdir apt-get install --no-install-recommends -y eatmydata
 	if [ -x $rootdir/usr/bin/eatmydata ] && \
 	# desktop
 	chroot "$rootdir" apt-get -y install mate-desktop-environment lightdm
 
+	if [[ $VARIANT != "usb" ]]; then
+		if [ $MESH_DESKTOP_BACKGROUND_IMAGE ]; then
+			if [ -f $MESH_DESKTOP_BACKGROUND_IMAGE ]; then
+				if [ -d $rootdir/usr/share/plymouth/themes/joy ]; then
+					cp $MESH_DESKTOP_BACKGROUND_IMAGE $rootdir/usr/share/plymouth/themes/joy/background.png
+				fi
+				if [ -d $rootdir/usr/share/plymouth/themes/lines ]; then
+					cp $MESH_DESKTOP_BACKGROUND_IMAGE $rootdir/usr/share/plymouth/themes/lines/background.png
+				fi
+				if [ -d $rootdir/usr/share/plymouth/themes/spacefun ]; then
+					cp $MESH_DESKTOP_BACKGROUND_IMAGE $rootdir/usr/share/plymouth/themes/spacefun/background.png
+				fi
+			fi
+		fi
+	fi
+
 	# browser
 	chroot "$rootdir" apt-get -y install iceweasel