use standard URLSearchParams insead of custom functions

package.json

@@ -9,12 +9,13 @@
   "author": "",
   "license": "ISC",
   "dependencies": {
-    "bootstrap": "^4.4.1",
-    "ejs": "^2.7.4",
-    "ejs-render-remote": "^1.0.7",
-    "es6-promise": "^4.2.8",
-    "i18next": "^15.1.3",
-    "i18next-browser-languagedetector": "^3.1.1",
+    "@ungap/url-search-params": "^0.1.4",
+    "bootstrap": "^4.3.1",
+    "ejs": "^2.6.1",
+    "ejs-render-remote": "^1.0.3",
+    "es6-promise": "^4.2.6",
+    "i18next": "^15.0.9",
+    "i18next-browser-languagedetector": "^3.0.1",
     "i18next-xhr-backend": "^2.0.1",
     "jquery": "^3.4.1",
     "page": "^1.11.5",
@@ -22,6 +23,6 @@
     "popper.js": "^1.16.0"
   },
   "devDependencies": {
-    "minifyfromhtml": "^1.1.7"
+    "minifyfromhtml": "^1.1.2"
   }
 }