添加部分注释，修复一些功能

hydro/model/blacklist.js

@@ -2,11 +2,15 @@ const
     db = require('../service/db.js'),
     coll = db.collection('blacklist');
 
-module.exports = {
-    add(ip) {
-        let expireAt = new Date(new Date().getTime() + 365 * 24 * 60 * 60 * 1000);
-        return coll.findOneAndUpdate({ _id: ip }, { $set: { expireAt } }, { upsert: true });
-    },
-    get: ip => coll.findOne({ _id: ip }),
-    delete: ip => coll.deleteOne({ _id: ip })
-};
+async function add(ip) {
+    let expireAt = new Date(new Date().getTime() + 365 * 24 * 60 * 60 * 1000);
+    return coll.findOneAndUpdate({ _id: ip }, { $set: { expireAt } }, { upsert: true });
+}
+function get(ip) {
+    return coll.findOne({ _id: ip });
+}
+function del(ip) {
+    return coll.deleteOne({ _id: ip });
+}
+
+module.exports = { add, get, del };