Threaded barriers into the client, not yet queried

I've also refactored the rooms slightly.

server/combat/barrier_data.cpp

@@ -27,6 +27,7 @@
 BarrierData::BarrierData(int i):
 	Entity::Entity("barrier")
 {
+	instanceIndex = i;
 	memcpy(status, 0, sizeof(int) * 8);
 }
 

server/combat/barrier_data.hpp

@@ -50,7 +50,7 @@ private:
 	int scriptRef = LUA_NOREF;
 	std::map<std::string, std::string> tags;
 
-	int instanceIndex = -1;
+	int instanceIndex;
 
 	int status[8];
 };