message: Make more linter warnings errors so that tests fail if we introduce new violations. Increase max nested callbacks to 4.
diff: "consistent-return": 0,
  "consistent-this": [1, "that"],
  "curly": [2, "all"],
  - "default-case": [1],
  - "dot-notation": [1],
  + "default-case": [2],
  + "dot-notation": [2],
  "eol-last": [2, "unix"],
  "eqeqeq": [2, "allow-null"],
  "guard-for-in": 2,
  "import/no-unresolved": ["error"],
  + "import/no-duplicates": ["error"],
  "indent": [2, 2, {"SwitchCase": 1, "VariableDeclarator": 2}],
  "jsx-quotes": "error",
  "linebreak-style": [2, "unix"],
  - "max-nested-callbacks": [1, 3],
  - "no-alert": 1,
  + "max-nested-callbacks": [1, 4],
  + "no-alert": 2,
  "no-caller": 2,
  "no-comma-dangle": 0,
  - "no-console": 1,
  + "no-console": 2,
  "no-constant-condition": 2,
  - "no-debugger": 1,
  + "no-debugger": 2,
  "no-else-return": ["error"],
  "no-global-strict": 0,
  "no-irregular-whitespace": ["error"],
  "no-trailing-spaces": ["error"],
  "no-underscore-dangle": 0,
  "no-unused-vars": ["error", {"varsIgnorePattern": "React"}],
  - "no-use-before-define": 1,
  + "no-use-before-define": 2,
  "no-var": 2,
  - "prefer-template": 1,
  + "prefer-template": 2,
  "quotes": [2, "single"],
  "radix": 2,
  "react/jsx-curly-spacing": 2,
  