This allows a texturepack to support both the
original hotbar (for release edition) and the new
hotbar (for the alpha edition) at the same time,
while giving us time to test out the alpha version
and roll out the new release when it's ready, and
without forcing TP authors to trade off support.
Names are also lexically consistent and more
consistent with internal names.
We still change the background, but only depend
on the state of the slot, not on wield index. Go
back to a traditional slot selection ring for the
selection index.
Slot backgrounds are a little bolder normally, and
when broken, especially bold around the broken
areas.
The selection ring itself is broken so that the
gaps in broken slots are still "open" to the outside
when the selection ring is in place.
- Highlight behind item may lag behind the
new cursor, but the new cursor will show
which slot you're trying to select when
scrolling rapidly.
- Also fix the margins/centering for hotbar
image.
Will have to see how this plays on the actual
MP server, where there's notable RTT lag.
