Improvements to the jsgui catalogue page

* Displays info on applications and entities
* Reworks js so it will be simple to add items in the future
* Adds two helper interfaces to summary objects in rest-server that enable simple sorting by name/id
* Temporarily removes ability to add new catalog items through UI.
Great that this will now be a consistent ordering on multiple calls. However, on different runs of brooklyn it will be listed in different orders. Should it use `nameComparator` instead?