tweak thumbnailer to not modify gifs and give good feedback

thumbnailer.sh

@@ -20,7 +20,11 @@ pathtrans() {
 
 resize() {
   output=$(pathtrans $1)
+  if echo $1 | grep .gif > /dev/null; then
+    return
+  fi
   if [ ! -f ${output} ]; then
+    echo "generating thumbnail for $1"
     convert $1 -strip -auto-orient -resize ${SIZE} -dither FloydSteinberg -colors 16 ${output}
   fi
   replace $1 ${output}
@@ -35,11 +39,14 @@ replace() {
   src=$(echo "src='${src}'")
   dest=$(echo "src='${dest}'")
 
+  echo -n "modifying html to use thumbnail for $1"
   for f in $(find ${ROOT}/*.html); do
-    if grep ${src} ${f}; then
+    echo -n "."
+    if grep ${src} ${f} > /dev/null; then
       sed -i s#${src}#${dest}# $f
     fi
   done
+  echo
 }
 
 echo "creating new thumbnails"