[pngzop] Added pngzdat tool to extract compressed IDAT data from a PNG.

pngzdat

@@ -0,0 +1,9 @@
+#!/bin/sh
+
+for x in $*
+do
+  root=`echo $1 | sed -e s/.png$//`
+  pngidat.exe < $1 > $root.zdat
+  ls -l $root.zdat
+  shift
+done