All packet creating methods now create Packet instead of byte[]

This commit got way too big...
- Remove deprecated methods for sending packets
- Favor OutPacket & Packet over MaplePacketLittleEndianWriter, LittleEndianWriter, and byte array
- Split up some packet creating methods into separate classes

src/main/java/net/server/channel/handlers/UseGachaExpHandler.java

@@ -50,6 +50,6 @@ public class UseGachaExpHandler extends AbstractMaplePacketHandler {
             }
         }
         
-        c.announce(PacketCreator.enableActions());
+        c.sendPacket(PacketCreator.enableActions());
     }
 }