Mention support for YouTube.com user videos in the documentation

documentation.html

@@ -53,6 +53,7 @@
 <li>YouTube.com.</li>
 <li>YouTube.com playlists (playlist URLs in "view_play_list" form).</li>
 <li>YouTube.com searches, using the special keyword "ytsearch" as a form of URL, as in "ytsearch:cute kittens". Do not forget the quotes if you want to include spaces in your search. Other variants are "ytsearchN" to download more than the first result, with N being a number, and "ytsearchall".</li>
+<li>YouTube.com user videos, using user page URLs or the specifc "ytuser" keyword.</li>
 <li>metacafe.com.</li>
 <li>Google Video.</li>
 <li>Google Video searches ("gvsearch" keyword).</li>