Click events fixed

• Reworked click event hand detection
• Fixed oak doors not being considered as usable blocks
• Fixed not being able to get event from non-usable item when clicking air
• Fixed several ways to skip event handling (to open locked chests)

In the end, I really wonder why Bukkit AIR material is considered to be a block...

Edit: Re-release to remove debug messages. I forgot to recompile after removing them from source.