Verify that ABM neighbor check is correct

[S-S-X]

If this is correct then just drop comment about it and close issue.
If this is not correct then obviously fix it (or leave comment about it, possibly pointing out what should be changed + bug label).
https://github.com/mt-mods/mineunit/blob/8fc399e1f597ab9a17e285d563aac895c50584dc/server.lua#L53-L68

[S-S-X]

ABM handling was updated (for performance) here #36, match_neighbor loop however is still the same and requires checking for correct behavior.

mineunit/server.lua

Lines 39 to 56 in 3ab99b0

	local function match_neighbor(pos, nodes, groups)
	-- TODO: Make sure this is how engine actually looks for neighbors
	local rnodes = core.registered_nodes
	for x=-1,1 do
	for y=-1,1 do
	for z=-1,1 do
	-- Skip pos itself
	if not (x == 0 and y == 0 and z == 0) then
	local node = world.nodes[core.hash_node_position({x=x,y=y,z=z})]
	local name = node and node.name
	if name and match_nodes(name, rnodes[name] and rnodes[name].groups, nodes, groups) then
	return true
	end
	end
	end
	end
	end
	end