fix typo [codeacadamy.com -> codecademy.com]
Merge pull request #72 from syk0saje/master

fix typo [codeacadamy.com -> codecademy.com]
Changed some spelling mistakes. khanacadamy => khanacademy
Merge pull request #79 from LumenTeun/master

Changed some spelling mistakes. khanacadamy => khanacademy
Rewording readme.
Reworking popup design.
Merge branch 'master' of https://github.com/russtaylor/habitrpg-chrome