# get the second script in
# http://veryuniquename.blogspot.com/2013/06/downloading-pivotal-tracker-attachments.html
# (I haven't requested author's permission to post his code here)
# and replace the last line with:
# curl --silent --cookie cjar --cookie-jar cjar --output "$OUT_FILE" "$BASE_URL$ATT_ID"
# (I had to quote $OUT_FILE so the filename could have spaces)