Adds ability to add error return documetation to the binder and class reference.
Usage example:
```C++
void MyClass::_bind_method() {
[..]
BIND_METHOD_ERR_RETURN_DOC("load", ERR_FILE_CANT_OPEN, ERR_FILE_UNRECOGNIZED);
}
```
One function of ConfigFile was changed as example.
* Allows calling into native extensions directly with a pointer
* Makes it easier to implement some APIs more efficiently
* Appears with a "*" in the documentation for the argument.
* Implementing the pointer handling is entirely up to the implementation, although the extension API provides some hint.
* AudioStream has been implemented as an example, allowing to create NativeExtension based AudioStreams.
* `_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.
If methods signature did not match, documentation is not merged. This is
a considerable source of annoyance for contributors and it happened as
a result of #4533, otherwise the documentation for constructors would
not be properly merged.
This PR modifies the logic introduced to only do the signature test on
constructors and operators (which are the only types of members that can repeat).
* New syntax is type safe.
* New syntax allows for type safe virtuals in native extensions.
* New syntax permits extremely fast calling.
Note: Everything was replaced where possible except for `_gui_input` `_input` and `_unhandled_input`.
These will require API rework on a separate PR as they work different than the rest of the functions.
Added a new method flag METHOD_FLAG_OBJECT_CORE, used internally. Allows to not dump the core virtuals like `_notification` to the json API, since each language will implement those as it is best fits.
Capsule height and radius setters can modify each other, rather than
using clamping, to avoid cases where values are not set correctly when
loading a scene (depending on the order of properties).
Inspector undo/redo:
Added the possibility to link properties together in the editor, so
they can be undone together, for cases where a property can modify
another one.
Gizmo undo/redo:
Capsule handles pass both radius and height values so they can be undone
together.
When a shader error is printed about a built-in shader, the origin
of the shader will now be recognizable immediately by looking at
the top of the printed shader code.
* Make Undo/Redo menu items disabled when clicking it does nothing.
* Context menu of `TextEdit`
* Context menu of `LineEdit`
* Editor's Scene menu
* Script editor's Edit menu and context menu (for Script and Text)
* Make editor undo/redo log messages translatable.
* Mark `UndoRedo`'s `has_{un,re}do()` methods as `const`.
* Expose `TextEdit`'s `has_{un,re}do()` to scripts since `{un,re}do()` are already available.
