Add more React and Enzyme rules

[lemonmade]

• No useless wrappers (<>{stuff}{andThings}</> > <div>{stuff}{andThings}</div>)
• React component should make every member private except React API stuff
• Enzyme no bad features (setState, instance, etc)
• Don't reach across component boundaries (good: ./components, ../components, components, ../OtherComponent. bad: ../OtherComponent/any-path, ./components/SomeComponent)
• Avoid renderFoo methods being explicitly called in render() (use components instead)
• Avoid using most raw DOM manipulation
• Avoid the word correct in test names

[alexandcote]

Most of the issues listed above are now solve. Feel free to reopen an issue if I missed something.