Stacking in any direction

Because it's terribly frustrating that it's impossible to make a grand staircase mine in worldedit. 

I tested this on a server a bit with some random mixture of brick and glass, and it didn't seem to mess up the pattern, so I think it's correctly copying with overlap (i.e. not using a copied block as a source to copy from).

//luatransform local name; if math.random() > 0.4 then name = "default:glass" else name = "default:brick" end; core.set_node(pos,{name=name})