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
Made NPCs now work properly on multiworld system. Solved multiple issues
regarding Player Shops not giving back items properly when owner exits.
Added restriction on changing channels at FM rooms, preventing shop
owner entering Cash Shop.