chore(lint): update eslint rules

[austingreendev]

Description

This PR is an audit of our existing ESLint rules. The only change is that we now require displayNames for all React components. This was disabled previously, but should be best practice for us going forward.

Checklist

• 👌 design updates are Garden Designer approved (add the
  designer as a reviewer)
• 🌐 Styleguidist demo is up-to-date (yarn start)
• ⬅️ renders as expected with reversed (RTL) direction
• ♿ analyzed via axe and evaluated using VoiceOver
• 💂‍♂️ includes new unit tests
• 📝 tested in Chrome, Firefox, Safari, Edge, and IE11

[coveralls]

Coverage increased (+0.08%) to 93.977% when pulling add6771 on agreen/eslint-alignment into f8f7068 on master.

[jzempel]

Looks like there should be a new require-display-name custom rule added for eslint under /utils.

[jzempel]

Please add displayName to the .template package.

[austingreendev]

Looks like there should be a new require-display-name custom rule added for eslint under /utils.

There is a lot of complexity in determining whether a displayName is valid. https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/display-name.md only missed 2 components due to our unique createPortal usage. We might want to stick with the existing solution to avoid complications as React introduces new APIs as well.

Please add displayName to the .template package.

Updated! 👍