* Trying to reduce memory leaks
* Formalize the usage of pianoVK.ctrl and pianoVK.shift
* Replace all loop, make a text object list
* Add auto-garbage cleaner and remove 2 unnecessary variable
* Update app_piano.lua
* Trying to reduce memory leaks
* Formalize the usage of pianoVK.ctrl and pianoVK.shift
* Replace all loop, make a text object list
* Add auto-garbage cleaner and remove 2 unnecessary variable