Add more info to docstring of generated methods

[AGlass0fMilk]

It would be useful for user clarity and tooltip generation in the lv_gui_builder if the docstring of generated methods had more information.

For example, right now, calling:

import inspect
import lvgl
inspect.getdoc(lvgl.Btn.set_auto_realign)

will print 'void lv_obj_set_auto_realign(lv_obj_t *obj, bool en)'. This is a good start. Perhaps this info could be formatted in such a way that it could be both human and machine-readable. A simple dictionary would do:

signature: void lv_obj_set_auto_realign(lv_obj_t *obj, bool en)
help: Enable autorealignment for this lvgl object

or something like that.