Hiding this broke the indentation for nested lists.  This reverts to something
like the default Doxygen style.

This removes all the extra bundle content from the documentation output and
instead makes pages directly at the URI of specifications.  This way, links to
fragments in spec pages (which are often copy and pasted) are correct fragment
identifiers like <http://lv2plug.in/ns/lv2core#Plugin> instead of
<http://lv2plug.in/ns/lv2core/#Plugin>.

This is moving to the homepage, since it clutters up the documentation less,
and can be syndicated that way.