Numpad Keycodes and Android Keycodes collides / Optimize generation of scancodes

[joBr99]

I've just found that my numpad is typeing chars in the english layout. For example Numpad 7 has JavaScript KeyCode 103 (0x67), which is also the KeyCode of 'g' on my android phone.

Android is sending always 229 as KeyCode to get around this I've seen that you are mapping the unicode position of the char to the scancode. Maybe we should always use the unicode way, except for the arrow keys and similar keys.

Open for good ideas to handle that problem...

[cnlohr]

I don't really have any input on this, I've been out of the project for so long, but if you can find a solution, please let me know and make a PR!