Plugins are used by the editor to extend functionality. The most common types of plugins are those which edit a given node or resource type, import plugins and export plugins. See also [EditorScript] to add functions to the editor.
[b]Note:[/b] Some names in this class contain "left" or "right" (e.g. [constant DOCK_SLOT_LEFT_UL]). These APIs assume left-to-right layout, and would be backwards when using right-to-left layout. These names are kept for compatibility reasons.