feat: Handle privilege escalation gracefully even without PolicyKit (#599)

* feat: Handle privilege escalation gracefully even without PolicyKit

* build: upgrade tslint => 5.9.1

* build: add uhk-agent/package-lock.json

* feat: add error animation

* fix: display agent icon when user use ALT + TAB

packages/uhk-agent/package.json

@@ -30,6 +30,7 @@
   },
   "scripts": {
     "start": "electron ./dist/electron-main.js",
+    "electron:spe": "electron ./dist/electron-main.js --spe",
     "build": "webpack && npm run install:build-deps && npm run build:usb && npm run download-firmware && npm run copy-blhost",
     "build:usb": "electron-rebuild -w node-hid -p -m ./dist",
     "install:build-deps": "cd ./dist && npm i",