Implement item class

[Smjert]

We need this class at least to give each item a durability/damage value.
We need it later for enchantment.
It must be decided if to follow the same pattern as blocks or making an instance per item since they are far less than blocks and since maybe some user wants to add special properties to specific instances (like having a super diamond pickaxe with 10 times the durability without making a new class for it).

[taugit]

I'm voting for instance per item way - the issue with blocks was that 1 chunk have 32k blocks which is a bit heavy. I doubt that we would have more than a thousand of items active (inactive items have to be saved in a chunk).
May I take this task? Anyway I was going to ask to take this task before, but left it since I had few more important tasks unfinished.

[Smjert]

Do it! :P, we need it done since there's few bugs with the set slot packet and items not enchantable, the -1 on the nbtcompound is sent when it shouldn't be sent so the client then reads wrong packets and disconnect.

[creatorfromhell]

I was reading over this issue and thought about how I would implement this if I was asked to. So I came up with this: http://www.mediafire.com/?thp8ye984layoih . Now I tried to comment the code as much as possible and add the TODO's into the classes where they were needed.

[ementalo]

I would like @Gremlin13 to have a look over since he was doing some stuff on this

[creatorfromhell]

Ok. Sounds good.