[Kernel2.2] Remove nulls?

[Gianugo Rabellino]

I've seen in the new API that in a number of places there are contracts 
that return null if something isn't found: since these are all perfect 
candidates for nasty NPEs, how about switching to NullObject pattern or 
throw Exceptions instead?

Just my 0.2c, but since we're talking foundations I think it could be a 
right time to be strict about code principles...

Ciao,

--
Gianugo Rabellino
Pro-netics s.r.l. -  http://www.pro-netics.com
Orixo, the XML business alliance - http://www.orixo.com
    (Blogging at: http://www.rabellino.it/blog/)