feat(eslint): upgrade ESlint to v5

BREAKING CHANGE:

Author: robertrossmann

README.md

@@ -1,7 +1,7 @@
 [eslint-url]: http://eslint.org
 [travis-badge]: https://travis-ci.org/strvcom/eslint-config-javascript.svg
 [travis-url]: https://travis-ci.org/strvcom/eslint-config-javascript
-[eslint-version]: https://img.shields.io/badge/ESLint-^4.19.1-brightgreen.svg
+[eslint-version]: https://img.shields.io/badge/ESLint-^5.0.0-brightgreen.svg
 [eslint-fixing]: http://eslint.org/docs/user-guide/command-line-interface#fix
 [flow-home]: https://flow.org
 [react-home]: http://reactjs.com

coding-styles/recommended.js

@@ -23,9 +23,7 @@ module.exports = {
     // This rule looks for any underscores (_) located within the source code. It ignores leading
     // and trailing underscores and only checks those in the middle of a variable name. If ESLint
     // decides that the variable is a constant (all uppercase), then no warning will be thrown.
-    camelcase: ['warn', {
-      properties: 'always',
-    }],
+    camelcase: ['warn'],
 
     // Require Consistent This
     // This rule designates a variable as the chosen alias for `this`.