New design is bound to BrowserRootCategories collection

New design is bound to BrowserRootCategories collection. There are some bugs but we have something to show. Works correctly for Geometry category. Possible too long names of some functions. For example: `Geometry.Cuboid`.

@Benglin, please review.
Please see [this comment](https://github.com/DynamoDS/Dynamo/pull/2128#discussion-diff-16102156) in another pull request for details of how this can be removed (I think it has been removed, but not sure where we are).