message: update manifest version to v2.0.0
diff: {
  "name": "Recoilize",
  - "version": "1.0.0",
  + "version": "2.0.0",
  "devtools_page": "devtools.html",
  "description": "A Chrome extension that helps debug Recoil applications by memorizing the state of components with every render.",
  "manifest_version": 2,
  