Anycubic Mega i3 Ultrabase cable support

I found that the version by hampisch (https://www.thingiverse.com/thing:2266134) didn't quite fit around the cable connector on my MEGA so I modified it to allow more space.

Since the Ultrabase version doesn't include the bed level sensor, it may be that the connector is a different size or position than the first version of the i3 Mega. If that's the case, this remix will fit better.

I also added a slot for a cable tie, but I ended up not using it.

This may work for other variations of the Anycubic Mega, however it does not fit the Mega Pro.