Multi-protocol

Lots of chagnes to add multi protocol flexibility, not really
completed yet, still have to rework text messages opcodes and other stuff,
so this still a working in progress feature

* Rework dat reader, the dat reader can now
* dinamically detect dat version
* Split game into gamelib and game_interface
* Lots of other minor changes

modules/gamelib/protocolgame.lua

@@ -0,0 +1,23 @@
+local opcodeCallbacks = {}
+
+function ProtocolGame:onOpcode(opcode, msg)
+  for i, callback in pairs(opcodeCallbacks) do
+    if i == opcode then
+      callback(msg)
+      return true
+    end
+  end
+  return false
+end
+
+function ProtocolGame.registerOpcode(opcode, callback)
+  if opcodeCallbacks[opcode] then
+    error('opcode ' .. opcode .. ' already registered will be overriden')
+  end
+
+  opcodeCallbacks[opcode] = callback
+end
+
+function ProtocolGame.unregisterOpcode(opcode)
+  opcodeCallbacks[opcode] = nil
+end