- Further simplifies their appearance and
registration code
- Makes stacks on ground consistent with stacks
on shelves.
- Makes stacks-on-stacks look a litlte less silly.
- Eliminates spurious implication that stack
nodes might block light, which they don't
necessarily do.
If a node is specially tagges with the stack_as_node group, and
the stack size is exactly 1, place as a real node instead of a
stack node.
This reinstates logic from WAY back in the super-early pre-alpha
days, except only for nodes explicitly tagged this way.
This should be applied only to nodes that aren't transformed in
any non-desirable way when placed as nodes instead of stacks, and
can be dug the same ways as stacks (i.e. snappy = 1 or
crumbly = 1).
Currently applied to sticks, staves, leaves, ladders/frames,
and torches. Ladder/frame placement offers some interesting
possibilities in terms of throwing ladders to rappel down holes.
When removing a stack, if there is a stack above, move it
immediately into place of the removed stack. This works
recursively, so stack nodes never have a chance to break out
into item entities, fall to the bottom and make a huge mess.
Unfortunately there isn't a very good visual for the stack
shifting down yet, but at least the gameplay is there.
