paddingX and paddingY

[opsb]

trafficstars

I've found a couple of scenarios that pop up frequently:

1. I want to set padding on a single axis
2. I want to set padding on a single axis and then add a single side in the other axis

In the case of (2) it seems quite natural to do

, paddingX = 20
, paddingBottom = 10

rather than have a paddingSomething that takes padding for all 4 sides.

[mdgriffith]

Ah, interesting, yeah my stacking logic doesn't quite allow that. Ok, I'll put it up for review for v3.2!