Dis1189 discussion top comments

This is a pull request for a feature that is currently in a lot of flux but that needs to be merged for user testing purposes.

The top comments module design is still not signed off so in its current state there are a lot of cross module hacks and calls and the script in-particular is not organised well. Once a design is signed off then the modules can be properly organised to ensure SOC and a refactoring/re-architecting of the discussion app can/will take place.

For the time being though the code needs to be available in its current state for a user testing workshop.

An (incomplete) list of issues that will need to be addressed before this code is at a good standard.

 - Reorganisation/rearrangement of Loader, Comments and TopComments component modules.
 - Elimination of cross module element hooks and method calls (can be fixed once component boundaries are found from final design)
 - Refactoring of HTML out of Article application and in to Discussion application.
 - Finalisation of CSS and cross browser concerns once design is final.
 - Extra commenting once all else is finalised.