Mostly to use the images and css files under doc/src instead of
doc/html, usually be deleting the settings in order to use the defaults.
Also add 'boost.root' to some builds in order to fix links which rely on
it.
[SVN r63146]
Tweaked some existing Jamfiles so that PDF build finds all the necessary image files etc.
Tweaked fo.xsl to provide more options by default, and improve formatting.
[SVN r51104]