Adding add and subtract to hash - add to active support?

Giles Bowkett created a simple implementation of hash + other_hash,
and hash - other_hash.

http://gilesbowkett.blogspot.com/2007/12/hash-math-and.html

I'd say it makes sense to add that into active support.

Not as a ticket - http://dev.rubyonrails.org/ticket/10503