make navigation list shorter
make navigation list shorter

No need to show the last level in general, since it is now clear from
the <h2> tag where we are.

famz/patchew,patchew-project/patchew,patchew-project/patchew,famz/patchew,patchew-project/patchew,famz/patchew,patchew-project/patchew,famz/patchew