adding pncrush script to make pngs smaller

scripts/pngcrush

+#!/bin/sh
+
+# there can be as many input arguments as you want
+# they are all assumed to be PNG file names
+
+# run as sh pngcrush $(ls *png)
+
+# loop through all arguments
+while (( $# >= 1 )); do
+	# create temp output file
+	# output file has all colorspace chunks removed and optimized compression
+	pngcrush -l 9 "$1" "$1".tmp
+	# remove the original file
+	rm "$1"
+	# replace the original with the new optimized output file
+	mv "$1".tmp "$1"
+	shift
+done
+
+exit 0
+
+# from http://cvs.sourceforge.net/viewcvs.py/tom7misc/vstplugins/scripts/fixpng?rev=1.2&view=auto