[development] Recent menu patch mandates a truncate cache

[Karoly Negyesi]

Hi'

Some of us may have already greeted by 'Page not found' everywhere in a  
recent HEAD. You need a menu_rebuild but as the UI is dead you need to  
truncate your cache table from database prompt.

I am not filing a separate issue as this is fixed in drumm's update /  
install patch.

Regards

NK