@Override
    public void onAction(String name, boolean isPressed, float tpf) {
        if (monitors == null) return;

        if (name.equals("down") && isPressed) {
            monitorSelected++;
            if (monitorSelected >= monitors.size()) monitorSelected = 0;
            saveSettings();
        } else if (name.equals("up") && isPressed) {
            monitorSelected--;
            if (monitorSelected < 0) monitorSelected = monitors.size() - 1;
            saveSettings();
        } else if (name.equals("fullscreen") && isPressed) {
            settings.setFullscreen(!settings.isFullscreen());
            saveSettings();
        }
    }
Tests the capability to change which monitor the window will be created on.
Also, shows that you can force JME to center the window. Also, it shows to to
force JME to set the window to x,y coords. Center window and window position
doesn't apply if in fullscreen.

@author Kevin Bales
jme3-examples/src/main/java/jme3test/app/TestMonitorApp.java