Implement networking system for when in levels

[Phabbits]

Context
There needs to be a system of messages between the client and the server to keep every player up to date with what is happening.

Idea
We have discussed running a version of the game both on the client and the server to mimimize the amount of messages needed to be sent, in contrast of having the client sending just its player's input to the server, and the server sending back what to draw.

Solution or next step
To complete this we will need the following messages sent:

• Player position and latest bullet to Server
• All player positions and latest bullets to Clients
• Player interaction with items, pick up/drop to Server
• All new item interaction to Clients
• Occasional syncing of all enemies