[macOS] Fix transient windows not working in the full-screen mode.
[macOS] Fix moving transient windows to the other screen than parent window.
[macOS] Fix popup menu switch on hover.
[macOS] Use content origin rect for windows position (to ensure `DS.mouse_get_position` is equal to `DS.window_get_position` + mouse position from the input events).
[macOS] Fix incorrect input coordinates, when external display with different scaling in connected/disconnected.
[macOS/Windows] Fix moving fullscreen windows between the screens.
Add auto refocusing of the parent window, when the focused transient window is closed.
Remove redundant `DS.mouse_get_absolute_position` function (returns mouse position in the screen coordinates, same as `DS.mouse_get_position`).
* `_gui_input`, `_input`, `_unhandled_input` and `_unhandled_key_input` are now regular C++ virutal functions.
* Everything else converted to GDVIRTUAL
* BIND_VMETHOD is gone, always use the new syntax from now on.
Creating `_gui_input` method and using the binder to register events will no longer work, simply override the virtual function now.
* Added explicit return type to the SNAME macro.
* Add some extra SNAME usages.
* Change some ClassDB methods to use const StringName & arguments.
* Cache the Window parent in Control because it's used in
is_layout_rtl(), which is called often.
* Only enable internal processing for viewports that need it.
* Change CanvasItem::group to be a StringName because it's only used as
that.
* Added a new macro SNAME() that constructs and caches a local stringname.
* Subsequent usages use the cached version.
* Since these use a global static variable, a second refcounter of static usages need to be kept for cleanup time.
* Replaced all theme usages by this new macro.
* Replace all signal emission usages by this new macro.
* Replace all call_deferred usages by this new macro.
This is part of ongoing work to optimize GUI and the editor.
* Added option for importers to show an Advanced settings dialog
* Created advanced settings dialog for Scene Importer
* Cleaned up importers (remove many old/unused options)
* Added the ability to customize every node, material, mesh and animation individually
* Saving to animations and meshes to files is now a manual process, making it more predictable
* Added the ability for materials to be replaced by external files (or to be made external, up to you).
* When doubleclicking an impoted scene in the filesystem dock, it automatically shows the import settings instead of asking to open it.
WARNING: Lightmap UV unwrap is not working, it needs to be re-made.
