Riot v4 and better folder structure

• Upgrade Riot to v4 from v3 which is a complete rewrite
  • Mixins are removed in favour of plugins
  • CSP is supported automatically
• Organization of files for easier understanding
  • background, popup and chrome api
• Reuse of code wherever possible
• Testable code structure (Previously mixins were omitted now plugins are also tested)
• Documented methods

Fix vulnerabilities and upgrade packages

• Vulnerabilities detected by github and yarn audit have been fixed.
• Babel has been upgraded to version 7 from 6 which is a notable change.
• Riot has been upgraded to v3.13.2.
• Other packages such as webpack have also been upgraded.

First Stable release

v2.1.0

Updated the changelog