Add support for Worlds

Added

• Add support for the League of Legends World Championship
• Add update notifications
• Add new test cases for getDate function

Changed

• Require Node.js 10
• Update all packages
• Rename Changelog.md to CHANGELOG.md
• Add an unreleased section to CHANGELOG.md
• Change example images in README.md
• Code readability improvements
• Underline winning team instead of displaying star symbol
• Fix typo in README.md

Fix issue with date header

Changed

• Fix issue with date header not displaying for first match of the week.