* eslintrc: adapt changes in eslint-plugin-jsx-a11y

* Replace 'jsx-a11y/img-has-alt' with 'jsx-a11y/alt-text'.
  Reference: evcohen/eslint-plugin-jsx-a11y@24b6193

* Replace 'jsx-a11y/onclick-has-focus' with 'jsx-a11y/interactive-supports-focus'
  Reference: evcohen/eslint-plugin-jsx-a11y@cbdfeb8

* Replace 'jsx-a11y/onclick-has-role' with 'jsx-a11y/no-noninteractive-element-interactions'
  Reference: evcohen/eslint-plugin-jsx-a11y@18c9b71

* Update eslint-plugin-jsx-a11y to 5.0.0

Follow the change in Code Climate. Make sure the same eslintrc
can be executed locally and in Code Climate.

* Convert .eslintrc.json to equivlant .eslintrc.yml

* Less quotes and commas, more readability, allow comment.