RSS Feed is too large
Hi,

I'm generating an RSS feed (you can see my set-up here: https://github.com/Integralist/Website and the distributed version here: https://github.com/Integralist/integralist.github.com) but I'm using Feedburner and it refuses to now update my feed (partly) because the size of the feed is too large...

```
Your feed filesize is larger than 512K. 
You need to reduce its size in order for FeedBurner to process it.
```

...this is because the feed.xml being generated includes the entire contents of my articles rather than a short description.

Is there any way to use a short description (I have one defined as meta data in each of my posts).
