Bukkit

• Rewrote the method for determining if a player is looking at a sign; it's much more robust and flexible. This fixes apparently random cases when SignBoard would not show a board even though the player was looking at the sign. Also allows players to look at signs from any angle.
• Implemented '/sb entity' commands to allow attaching boards to living entities - animals, monsters, villagers, NPCs...
• Upon start up, SignBoard now checks for "defunct" signs in signs.yml and attachments.yml and deletes them. If the server is run without loading SignBoard and any signs are deleted (broken in-game), they will no longer exist in the world, but will remain in signs.yml and attachments.yml. The new automatic "cleanup" function during SignBoard start up takes care of that.
• Made a number of small performance improvements in the code.

None at this point. Looking forward to feedback.