Add server properties file

[arslee07]

I think it will be correct if we add a file in which it will be possible to change the properties of the server, for example, its port, the maximum number of players, etc.

[tazz4843]

Will be done once fundamental parts of the server (threading, networking, etc) are all working properly.

[ghost]

Exceedingly useful module which you should absolutely use to do this https://pypi.org/project/toml/

(if you don't want it to be strictly compatible with the original server)

[randomairborne]

I could make a GUI to set this up