feed-cli: A simple command line interface for creating and updating feeds like RSS

See my announcement:
http://www.syntaxpolice.org/index.php/?q=node/425

Synopsis:

This program generates [RSS 2.0 http:\/\/www.rssboard.org\/rss-2-0-1-rv-6] 
feeds based on command line arguments.  Use it to create and update feeds
from shell scripts, build scripts, cron jobs, CGIs, or other programs instead
of using an RSS or Atom library.

Commands and args:

new-item: -iFILE (required, or -u): The feed to add this item to
          -oFILE (optional): otherwise, stdout
          -tTitle (required)
          -dDescription (required, or -D, or --pipe-mode)
          --pipe-mode: read description from STDIN
          -lhttp://example.com (optional): Item link
          -DFILE: read description from a file
          -uFILE (optional): Update this file, not valid with -i or -o. Same as -iFILE == -oFILE
          --limit (optional): Keep the number of items fixed. Drop the last item when adding a new item. Doesn't compare dates yet. Taken from the front since that's how we add them.
          --limit=NUM (optional): keep only the last NUM items.

new-feed: -oFILE (optional): otherwise, stdout
          -tTitle (required): feed title
          -dDescription (required): feed description
          -lhttp://example.com (required): Feed link

EXAMPLES:

See also the patterns directory.

# create an empty feed:
./feed-cli new-feed -tTitleOfFeed -d"Feed Description" -o/tmp/feed.xml  -lhttp://www.syntaxpolice.org

# add an item to that feed 
./feed-cli new-item -t"entry of the day" -d"This is a description of <b>this feed item</b>." -u/tmp/feed.xml  -lhttp://www.syntaxpolice.org

# pipe a command into a feed item
ls -l | ./feed-cli new-item --pipe-mode --pre -t"another entry of the day" -u/tmp/feed.xml  -lhttp://www.syntaxpolice.org