This should have been an established process, but for some reason it was
edited manually after initial generation.
After the change `reference.xml` can be removed from the repository, but
I left it to show that the things are working fine and the difference from
an auto-generated one are simple divergences due to manual changing
(not updated `reference.xml` with added `<purpose>` elements in 38017203f69cec3aa5f402fe8306eb1deff67b9a). Also removed the date numbers
from `dtdxml` as they were never in `xml` and seems to have no actual use,
but brings a lot of noise to `xml` differences after added auto-generation.
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]
