+1 for a removeAll

While we're at it, I would like to add a "flatten" method to Collections.
This method removes all nesting from a collection (Strings are kept intact).
I find myself using this method regularily in Ruby and usually have to 
revert to inject:into: or local copies to achieve the same effect in 
Squeak. I implemented that method some time ago in my image, I added an
example and pushed that method to the inbox.

Regards,
Tim