Improve whitelist feature

* Use a primary autoincrementing primary key because primary keys need
  to be unique
* Cache whitelist on bot startup / only read from database once
* "Externalize" whitelist checking to the messageCreate function.

server.js

@@ -1,6 +1,7 @@
 const fs = require('fs');
 const createInitialConfig = require("./util/createInitialConfig")
 const convertJSONToSQL = require('./util/timer/convertJSONToSQL');
+const sqlite3 = require('sqlite3').verbose();
 if(!fs.existsSync("./data/config.json")) {
 	createInitialConfig();
 }
@@ -43,8 +44,36 @@ const {
 client.settings = new Collection();
 client.commands = new Collection();
 client.serverPrefixes = new Collection();
+client.whitelist = new Collection();
 
 
+
+async function loadWhitelist(clientWhitelist) {
+	const db = new sqlite3.Database('data/database.db');
+	let rows = await new Promise((resolve) => {
+		db.all(`SELECT * FROM whitelist`, function (error, rows){
+			if(error){
+				console.error("Failed to read whitelist table")
+				console.error(error);
+				resolve([]);
+			}else{
+				resolve(rows);
+			}
+		});
+	});
+	rows.forEach(row => {
+		if(clientWhitelist.has(row.serverId)){
+			let oldEntry = clientWhitelist.get(row.serverId);
+			oldEntry.push(row.command)
+			clientWhitelist.set(row.serverId, oldEntry)
+		}else {
+			clientWhitelist.set(row.serverId, [row.command])
+		}
+	});
+}
+
+loadWhitelist(client.whitelist);
+
 client.settings.set("presenceType", presenceType);
 client.settings.set("presenceText", presenceText);