Editor styles for annotations (text and region) using handler hooks and local config stores. Required adding support for remove_handler to the config Manager
Fix bug in annotation item focusing/config-handler switching
Fix bug in annotation item focusing/config-handler switching
Fix bug in annotation item focusing/config-handler switching
Improvements to structure of the GraphicsScene/View interactions.

Requires some testing to ensure all functionality is still working,
but greatly clears up interactions.
Add files for editor UI improvements.