Use moreblocks for building_blocks slab and stair
better handling of abusive sign input,
avoid breaking old signs' word wrapping

also increase the sign input limit to 600 chars, to allow for ample amounts of
color codes.
add cobwebs
make cobwebs walkable-through, also sunlight propagates.
give brass and wrought iron poles facedir
so they can be rotated to horizontal with screwdriver.