Customizable cat toy ball v2

So [my previous cat toy ball generator](http://www.thingiverse.com/thing:795052) was very popular, but despite all the options, I didn't like the way it actually printed. Mine had trouble staying put because of the small surface area touching the base, and all those little holes got a bit stringy.

The idea for this one came to me today -- each hole is reinforced with a ring that just touches the inner and outer walls at the edges, so it's stronger, and the face of the ring provides enough surface area for a nice, rigid print.

As before, you can still throw some pennies or bells inside it during the print!