* As a test, used by:
* Object buttons, tried to make it match the mockup.
* Text window header.
* Text window properties panel.
* Panel interaction with view2d is still problematic, need to make
this work properly still.
* Templates are very basic, the ones there are simple but already
can follow the object buttons mockup quite closely.
* It's based on a three level system: panels, templates and items.
To get an idea of what that means in practice, see:
http://wiki.blender.org/index.php/BlenderDev/Blender2.5/UI_LayoutEngine#Panels.2C_Templates_and_Items
