lower-case html names

[Graham Percival]

Jan,

I like the changes to the @uref{} links, but we should be able to
make all the html filenames lower-case by changing 2 or 3 lines in
the texi2html-init file.  I'm still not certain whether makeinfo /
info is happy with lower-case node names, so I think the perl lc()
function is better than manually renaming the nodes.

Could we hold off on the @ref{} and @rgeneral{} changes for a few
days while I take a look at this?

Cheers,
- Graham