full path to the source .sgml file in the repository included within it.
Not all .html files are generated from .sgml files in the same directory,
this makes finding the source .sgml from the .html file a little easier.
No objections from: Wolfram
Yes, this is supposed to be a new top level in the repository.
For the moment any changes to this area must be cleared by myself
or Jordan. Once the kinks are worked out, the policy will probably
be relaxed.