add legacy support of checkbox, add documents for cookie/lgres/request

lib/utility/lgres.js

@@ -51,19 +51,25 @@ async function doRefreshLgres(template) {
     const r = await get(`language/${lgid}${template}`);
     const dict = await r.json();
     localStorage.setItem(getStorageKey(lgid), JSON.stringify(dict));
-    cache = dict;
     return dict;
 }
 
 async function refreshLgres(template, lgres) {
     if (lgres == null || typeof consts === 'undefined') {
-        return await doRefreshLgres(template);
+        lgres = await doRefreshLgres(template);
     }
     const ver = Number(consts.resver);
     if (isNaN(lgres.ver) || isNaN(ver) || ver > lgres.ver) {
         console.log(`found new language res version: ${lgres.ver} => ${ver}`);
-        return await doRefreshLgres(template);
+        lgres = await doRefreshLgres(template);
     }
+    Object.defineProperty(lgres, 'r', {
+        writable: false,
+        configurable: false,
+        value: function (key, defaultValue) {
+            return getLanguage(this, key, defaultValue);
+        }
+    });
     cache = lgres;
     return lgres;
 }