Add persist plugin

src/models/PersistedData.ts

@@ -0,0 +1,26 @@
+import Model from "./Model";
+
+export default class PersistedData extends Model {
+  private _roles;
+  private _isVoiceMuted;
+
+  public guild_id: string;
+  public user_id: string;
+  public nickname: string;
+
+  set roles(v) {
+    this._roles = v ? v.split(",") : [];
+  }
+
+  get roles() {
+    return this._roles;
+  }
+
+  set is_voice_muted(v) {
+    this._isVoiceMuted = v === 1;
+  }
+
+  get is_voice_muted() {
+    return this._isVoiceMuted;
+  }
+}