Fixed player moving between worlds.

Fixes FS #407.
Also fixes a few possible deadlocks between SocketThreads and TickThread

git-svn-id: http://mc-server.googlecode.com/svn/trunk@1641 0a769ca7-a7f5-676a-18bf-c427514a06d6

source/World.cpp

@@ -1843,6 +1843,8 @@ void cWorld::AddPlayer(cPlayer * a_Player)
 	
 	m_Players.remove(a_Player);  // Make sure the player is registered only once
 	m_Players.push_back(a_Player);
+	
+	// The player has already been added to the chunkmap as the entity, do NOT add again!
 }