Version 6.0.0

Major

• Updated Node.js support from v8.10+ to v10+.
• Updated dev dependencies, some of which now require Node.js v10+.

Patch

• Updated dependencies.
• Removed the now redundant eslint-plugin-import-order-alphabetical dev dependency.
• Stop using husky and lint-staged.
• Use strict mode for scripts.
• Fixed page getInitialProps not working when withGraphQLApp decorates an app that doesn’t have getInitialProps.