To ensure easier development and maintenance, IE support is dropped to allow
modern Javascript features. The old tabber module is rewritten into newer
standard and using classes to ensure proper scoping.
* Add basic inspector tool for tabbertransclude
* Add custom icon for Tabber
* Fix an issue where Tabber VE dialog is triggered when selecting mapframe
Adding some basic support for visual editing in VisualEditor. Currently it is nothing fancy, just the ability to recognize <tabber/> tags and a simple dialog with code editor to edit the Tabber code. It would be iterated upon in the future.