- [X] Converts boat packets
- [X] Makes a packet container builder for packet 0xF7
- [X] Generalizes world item packet so it works for mobiles too
Notes:
- This PR doesn't address proper smooth movement for boats.
- [X] Removes 6017 handler since it is only used in one place
- [X] Exposes a ref int to modify the packet length. This is acceptable since we technically have access to the entire reader/buffer.