This function is called everytime a key is pressed.
When the button is held for a little bit longer, this function will be called multiple times with isrepeat
as true.
Important Note: Besure to call Controls("keyboard") in the first line of the game !
Another Note: The keyboard on android can be closed by the user, so to reshow it you should call textinput(true)
in _touchpressed callback.
function _keypressed(key,scancode,isrepeat)
--Do something here
end