Change Meta key to Super

[lecormi]

For Linux, the modification makes it possible to simulate the pressing of the "Windows" key which is Super when simulating the pressing of the key key.Code.META. Indeed, knowing that the key has been associated on Windows to the "Windows" key (winuser::VK_LWIN) and on Mac OS to the "Apple" key (event::KeyCode::COMMAND), it seems more coherent to point to the Super key on Linux (key code X11 ``XK_Super_L```).
In any case, it would probably have been better to call this key "Super" and not "Meta" in the code, even if it means creating support for the "Meta" key separately (which is a very rare key, only existing on Sun computer keyboards according to Wikipedia).

[herbert-j-gamer]

I just debugged this issue and came up with the same solution. "Meta L" ends up being interpreted as "Alt" on my system. It should use "Super L" for the "Windows" key.