feat: add in immutable plugin for ESLint

Author: RyanTheAllmighty

packages/eslint-config-atlauncher/.eslintrc

@@ -3,6 +3,7 @@
         "./index.js"
     ],
     "rules": {
+        "immutable/no-mutation": "off",
         "filenames/no-index": "off",
         "import/unambiguous": "off",
         "quote-props": ["error", "consistent"]

packages/eslint-config-atlauncher/index.js

@@ -10,6 +10,7 @@ const rules = [
     // eslint plugins
     './rules/plugin-atlauncher',
     './rules/plugin-eslint-comments',
+    './rules/plugin-immutable',
     './rules/plugin-import',
     './rules/plugin-jsx-a11y',
     './rules/plugin-promise',
@@ -21,6 +22,7 @@ module.exports = {
         '@atlauncher/atlauncher',
         'eslint-comments',
         'filenames',
+        'immutable',
         'import',
         'jsx-a11y',
         'no-empty-blocks',