Make cookies valid across the entire site.

Signed-off-by: Sam Kleinman <samk@10gen.com>
New cookie key name

Signed-off-by: Sam Kleinman <samk@10gen.com>
Add a 'change versions' link in the sidebar

Signed-off-by: Sam Kleinman <samk@10gen.com>
giza: generation
minor: simplify code