refactor: rewrite OAuth and Requester (#90)

* chore: update type declarations

* dev: refactor oauth & requester

* chore: tidy things up

* chore: remove unneeded check

lib/parser/contents/classes/livechat/RemoveBannerForLiveChatCommand.js

@@ -0,0 +1,11 @@
+'use strict';
+
+class RemoveBannerForLiveChatCommand {
+  type = 'RemoveBannerForLiveChatCommand';
+
+  constructor(data) {
+    this.target_action_id = data.targetActionId;
+  }
+}
+
+module.exports = RemoveBannerForLiveChatCommand;