v6.2.0

This turns off a few rules that we have found to either be unused or too noisy in production:

• max-nested-callbacks: Only an issue and too noisy in tests
• react/display-name: Babel does this for us now that we use classes
• react/jsx-handler-names: Too noisy and doesn't always make sense
• react/prefer-stateless-function: We don't widely use these yet