Cont. (working on how-to-use.md)

Thinking about adding:
1. region.trigger('region:load-view', 'ViewName') for default context
region swap listener;
2. add advanced View type List/Tree, Panel/Tab and Table into
app.create('Regional') in addition to Item/Layout/Collection/Composite
(split Regional into 'Classic' and 'Advanced')

Note that we still maintain the View listing in Layout.Views static var.