[xhtml-basic] Typos (and the like)

In <http://www.w3.org/TR/xhtml-basic/>
(<http://www.w3.org/TR/2008/REC-xhtml-basic-20080729/>, to be
precise), there are at least two typos, "settop" (AFAIK it's typically
"set-top") and "implemententation". Apart from that, Alessio
Cartocci's and Luca Mascaro's affiliations problably don't deserve two
"li" elements each. ;)

-- 
Jens Meiert
http://meiert.com/en/