[development] Drop-down primary-links

[Nedjo Rogers]

Spurred by this discussion (I had one of those 'ah, this is how we could do 
it' moments), I've posted a patch to the activemenu module that will add 
multi-level drop-downs to primary links. It needs a fair bit of css work 
(briefly explained in the issue). If anyone wants to take on the css work, 
or other refinement, please post improvements to the patch:

http://drupal.org/node/127722

(I will be travelling for the next couple of weeks so will review any 
improvements after I'm back.)