Work with closed branches (BB-747)

In the latest mercurial versions the ability to close branches was added, but bitbucket shows all branches, even closed with //hg commit --close-branch// - it can be a little annoying. Here is an example: http://bitbucket.org/brainerazer/closed-branches-test/. As you can see when you clone it, it has 2 branches, one of them is closed but bitbucket shows both in the //branches// menu. Fix it please.