Move Store into Buffers;

Also create Groups class which is an index of interfaces by group name.
Add alias_method `composition` which redirects to `views`.
Add tests for Group class.
Add missing exception.
Add #registered method to return all the names of the registered events.
Prefer #render over #output for client applications;

Rather than defining a method #output in your view class, use #render instead, this feels more 'frameworky'.
Be more explicit.
Add more documentation.
Add test for Vedeu.views
Hook into API::Composition and fix typo.
Extract #colour and #style attributes into Presentation class.
Use Helpers#style instead.