Updated n-Echo Prototype

The template requires two MT plugins to be installed, LastModified and MTPerlScript. LastModified is needed since MT doesn’t let you extract the date an entry was last modified, and MTPerlScript is needed for time conversions to UTC, which is the preferred format for dates.
Mark’s template included a method for including full content from posts as escaped HTML in the content entity. As this is undergoing some political debate, I have left it in but it is not used in my current feed. I have also changed the number of entries within the feed from 5 to 15, to match how MT produces its RSS feed.
There’s a lot of comments in the template, so read over them and strip them out so your feed doesn’t bloat.
Above all else, feel free to reuse this however you’d like; I’d appreciate a trackback if you do, though.