Wire tracking was rewritten for better performance.
Now leads display exactly at the center of the block (on 1.8 the offset is still slightly incorrect, but only slightly).
Thick wires are not appearing separated anymore (works only for newly placed wires). On 1.8 thick wires may sometimes render incorrectly, it looks like it's a client bug.
Now entity locations are offset when being checked whether they are in the chunks that loaded to player. This can fix invisible wires bug.
