Added mono-clearbg, check pngcrush actually works

Makefile

@@ -29,7 +29,7 @@ ICONDIR := ${OUTDIR}/icon
 TEXTVARIANTS := word tagline1 tagline2
 
 SOLIDTEXTBGS := $(TEXTVARIANTS:%=%-whitebg-blackfg) $(TEXTVARIANTS:%=%-blackbg-whitefg) $(TEXTVARIANTS:%=%-mono-blackbg-whitefg) $(TEXTVARIANTS:%=%-mono-whitebg-blackfg)
-CLEARTEXTBGS := $(TEXTVARIANTS:%=%-clearbg-blackfg) $(TEXTVARIANTS:%=%-clearbg-whitefg)
+CLEARTEXTBGS := $(TEXTVARIANTS:%=%-clearbg-blackfg) $(TEXTVARIANTS:%=%-clearbg-whitefg) $(TEXTVARIANTS:%=%-mono-clearbg-blackfg) $(TEXTVARIANTS:%=%-mono-clearbg-whitefg)
 SOLIDPICBGS := pictorial-whitebg pictorial-blackbg pictorial-mono-blackbg-whitefg pictorial-mono-whitebg-blackfg
 CLEARPICBGS := pictorial-clearbg
 SOLIDBGS := ${SOLIDTEXTBGS} ${SOLIDPICBGS}
@@ -60,6 +60,9 @@ ${BGS}: ${FILES}
 
 %.png: %.1.png
 	pngcrush "$<" "$@"
+	if ((`stat -c%s "$@"` > `stat -c%s "$<"`)) ; then
+		cp "$<" "$@"
+	fi
 
 %.1.png: %.svg
 	f="$@"