Require Node.js 10 and upgrade chalk

[coreyfarrell]

• add Node.js 14 to travis-ci
• update development dependencies

---

I attempted to update xo to 0.29.1 but this caused TypeScript errors:

  index.test-d.ts:4:1
  ✖  4:1   Unsafe call of an any typed value              @typescript-eslint/no-unsafe-call
  ✖  4:20  Unsafe member access .info on an any value     @typescript-eslint/no-unsafe-member-access
  ✖  5:1   Unsafe call of an any typed value              @typescript-eslint/no-unsafe-call
  ✖  5:20  Unsafe member access .success on an any value  @typescript-eslint/no-unsafe-member-access
  ✖  6:1   Unsafe call of an any typed value              @typescript-eslint/no-unsafe-call
  ✖  6:20  Unsafe member access .warning on an any value  @typescript-eslint/no-unsafe-member-access
  ✖  7:1   Unsafe call of an any typed value              @typescript-eslint/no-unsafe-call
  ✖  7:20  Unsafe member access .error on an any value    @typescript-eslint/no-unsafe-member-access

Odd note the rule names were not links to documentation, though my TypeScript abilities are very weak so I'm not sure I'd be able to fix this even with hints from the rules documentation.

ava produces a warning in node.js 14 but this doesn't seem to break the testing. Someone has already opened a PR against ava to fix that warning.

[sindresorhus]

I attempted to update xo to 0.29.1 but this caused TypeScript errors:

Yup. Known issue and fixed now.