Page Up / Page Down for presenter remotes

Thank you for this wonderful app, which I would love to use in my lectures.

My presenter remote (Logitech R400) sends Page Up and Page Down to change slides. It seems magicPresenter reacts to the left and right arrow keys, but not to Page Up and Page Down. It would be great if those keys could also go to the next and previous slide, since many remotes use them.

Page Up and page down have been added to the key codes used to change slides. Additionally, the extended preferences allow to customise key codes.