Add docs for using lighttpd as the webserver.

lighttpd could support rules like this, to add efficiency:

1. Aggressively cache all static files $HTTP["url"] =~ "\.(jpg|gif|png|css|js|htc)" { expire.url = ( "" => "access 1 years" ) }
2. Compress files for faster transfer compress.filetype = ( "text/plain", "text/html", "text/javascript", "text/css", "text/xml" )
   
   compress.cache-dir = <would need to set to something>?

I don't know if that is necessary or useful. Probably not a good idea
at this point, where the code is changing so rapidly: a 1 year cache
of javascript code could cause trouble. And i think the default
lighttpd.conf already compresses text/html, text/plain, text/css, and
application/x-javascript by default, so we're ok there (could add
text/javascript and text/xml, I guess).