support for more keys

[clankill3r]

At the time of writing this is the code that deals with the keyTyped support:

terminal_read_input_vk_keys((vk_key)-> {

            // in the processing source this is event.getModifiersEx();
            // Not sure if 0 is always fine in our case, but for now I don't need more.
            int modiefiers = 0; 
            char c_key = (char)vk_key;

            // This can probably done better, but the KeyEvent class
            // that oracle provides lacks some really usefull methods.
            // For example a static method to get the char of a VK_key...
            // https://stackoverflow.com/questions/62967633/get-char-of-vk-key
            switch (vk_key) {
                case VK_UP: 
                case VK_LEFT:
                case VK_RIGHT:
                case VK_DOWN:
                c_key = CHAR_UNDEFINED;
                break;
            }

            parent.postEvent(new KeyEvent(null, parent.millis(), KeyEvent.TYPE, modiefiers, c_key, vk_key));

        });

There are so much more keys that could be supported, but at the moment I have more pressing things to do. Also I'm on a laptop right now and I don't want to assume things work the first time...