implement auth plugins

[MobiusCraftFlip]

Implements auth plugins

example plugin:

module.exports = {
	onServerStart: (api) => {
	},
	auth: [
		{
			moduleName: "testlocal",
			auth: localAuth,
			isEnabled: () => true,

		}
	],
};

[brunnre8]

Please don't do back merges, they aren't necessary.
Rebase your changes instead.

Also, do you plan to actually PR this eventually? If yes that'll need some discussion as to what your plans are, how you think the API should look etc.