Fix luavgl obj property API

[XuNeo]

Fix #61

Try to set property in a fixed order using lvgl's property API for specified class.

Iterate all base classes.

1. check luavgl property table for a match
2. if not match, check lvgl's property API for this specific class.

If still no match,

1. check luavgl's style set API.
2. check lvgl's style property.