Fix HTTP documentation - Broken link at section 15.2 "see ??? for further details"

go to http://static.springsource.org/spring-integration/reference/htmlsingle/
section 15.2

see:

"
The easiest way to do this is to provide a servlet definition in web.xml, see ??? for further details.

"

The ??? is an empty anchor link and goes to http://static.springsource.org/spring-integration/reference/htmlsingle/#