[development] Rating module quality

[Moshe Weitzman]

> I disagree that rating and download numbers will result in similar
> values. There are large number of modules I've downloaded that I would
> rate poorly in several of those categories -- the fact that I've
> *investigated* something should not be taken as an indication of my
> *conclusion* about it.

i agree that voting would be useful. if it turns out not  tobe useful, 
we can ditch it or restrict voting to a certain roles (i.e. 'editor 
votes'). editor picked modules are common on mozilla extensions, 
download.com, versiontracker, etc.