Lua: Let MultiTextCusor::cursors return a table

There is a problem with sorting QList<QTextCursor> due to the
implicit sharing in QTextCursor. For now just convert the list
to a table which works with table.sort as well.

Change-Id: Ia9bb8c7b89b5cd19f7f111eeaa6fc3ea381774ea
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/lua/bindings/texteditor.cpp

@@ -164,7 +164,7 @@ void setupTextEditorModule()
             "mainCursor",
             &MultiTextCursor::mainCursor,
             "cursors",
-            &MultiTextCursor::cursors);
+            [](MultiTextCursor *self) { return sol::as_table(self->cursors()); });
 
         result.new_usertype<QTextCursor>(
             "TextCursor",