Started Rewriting Packet Handling

Started rewriting our packet handling code. Deleted PacketHandler in
favor of using sided (Server-, Client-) packet handlers to make it
easier to follow what's going on in our code. Added some event-based
handling of updates which greatly simplified signaling that data needs
to be sent, but it's not completely done yet.

StevenDimDoors/mod_pocketDim/Point3D.java

@@ -4,6 +4,8 @@ import java.io.Serializable;
 
 public class Point3D implements Serializable {
 
+	private static final long serialVersionUID = -9044026830605287190L;
+	
 	private int x;
 	private int y;
 	private int z;