message: upgrade libpng1.2 -> 1.6 in build release tarball script
diff: @@ -50,7 +50,7 @@ source net/instaweb/public/VERSION
  RELEASE="$MAJOR.$MINOR.$BUILD.$PATCH"
  CHANNEL="$1"
  -deps="libpng12-dev libicu-dev libssl-dev libjpeg-dev realpath build-essential
  +deps="libpng16-dev libicu-dev libssl-dev libjpeg-dev realpath build-essential
  pkg-config gperf unzip libapr1-dev libaprutil1-dev apache2-dev"
  if dpkg-query -Wf '${Status}\n' $deps 2>&1 | \
  grep -v "install ok installed"; then
  