Attempt to debug lwjgl2

Text input on 1.12.2 and below are not working for some reasons...

JavaApp/src/main/java/org/lwjgl/opengl/GLFWInputImplementation.java

@@ -178,6 +178,7 @@ public class GLFWInputImplementation implements InputImplementation {
         last_event_nanos = nanos;
     }
     public void putKeyboardEvent(int keycode, byte state, int ch, long nanos, boolean repeat) {
+        System.out.println("LWJGL2: debug keyboard=" + keycode + ", state=" + state + ", repeat=" + repeat);
         key_down_buffer[keycode] = state;
         keyboardEvent.clear();
         keyboardEvent.putInt(keycode).put(state).putInt(ch).putLong(nanos).put(repeat ? (byte)1 : (byte)0);