Hi,I did some refactoring on master branch to deprecate interface org.apache.wicket.util.IProvider and use java.util.function.Supplier (and lambdas) in its place. It's not a huge work but i'd like to have some feedbacks before merging it into master. You can see the changed code here: https://github.com/bitstorm/wicket/commit/9c100492f5604521ab87459fe9eb17af0171d2c1
Andrea.
