core: allow setting priv_default

packages/hydrooj/src/model/user.ts

@@ -195,7 +195,7 @@ class UserModel {
     @ArgMethod
     static async create(
         mail: string, uname: string, password: string,
-        uid: number = 0, regip: string = '127.0.0.1', priv: number = PRIV.PRIV_DEFAULT,
+        uid: number = 0, regip: string = '127.0.0.1', priv: number = system.get('default.priv'),
     ) {
         const salt = String.random();
         if (!uid) uid = await system.inc('user');