Link µGFX licence source code 2.8

[Paul Christopher]

The link to the licence as given in the source code of version 2.8 seems to be wrong

/*
 * This file is subject to the terms of the GFX License. If a copy of
 * the license was not distributed with this file, you can obtain one at:
 *
 *              http://ugfx.org/license.html
 */

http://ugfx.org/license.html does not work. Should link to https://ugfx.io/license.html??

[Joel Bodenmann]

Thank you for bringing this to our attention!