World refactor

[RileyEv]

Changes:

• Network packets sending locations now use a struct PlayerPostion containing all position data.
• Now a player class to store all details about each player.
• Split world into a server/client world to allow for specific methods without confusion
• Renames PlayerSpawner
• Creates a player options struct to store all players options, such as car colour, player name, and car model.
• Creates enum for each car model, with extension method to easily get the prefab.
• Players are created in the world when they connect to the server.
• Players are still spawned when the game starts.
• Implements a new packet to inform already connected clients of new clients
• Changes Handshake events to support sending PlayerOptions
• Changes destroying of players in the world to destroy them on any disconnect event, not just ones occurring while a game is in progress.

Resolves #206 Resolves #207 Resolves #208 Resolves #217

[RileyEv]

Need to fully test on Mac

[RileyEv]

@ChrisGora can you re-review tis blocking the merge 😄

[RileyEv]

Added extension methods to get size of vectors, quaternions, colours, player positions and player options, makes typing packet lengths easier.