Add group chat functions, slight refactoring

src/factories/ChatFactory.js

@@ -0,0 +1,16 @@
+'use strict';
+
+const PrivateChat = require('../structures/PrivateChat');
+const GroupChat = require('../structures/GroupChat');
+
+class ChatFactory {
+    static create(client, data) {
+        if(data.isGroup) {
+            return new GroupChat(client, data);
+        }
+
+        return new PrivateChat(client, data);
+    }
+}
+
+module.exports = ChatFactory;