Refactoring/update count

IMO, updateCount method can be removed entirely and the all the logic related to displaying todo list stats in the footer can be expressed declaratively in the template. So a few things are happening here:

1. Footer template got additional markup to support data display in the footer.
2. updateCount method removed entirely from the layout class
3  serializeData introduced to provide data context for the template
4. A template helper is used to provide an easy way to build a label for the footer
5. ui hash is cleaned up to remove unused shortcuts