Create file popup.html
Add browser-action
Create image icon-16.png
Create image icon-48.png
Create image icon-128.png
Add icons
Add permissions
Add list of sites
Create file popup.js
Add script popup.js
Create directory sites
Create file delicious.js
Create file reddit.js
Add listeners for event click
Add function registerSite
Change function registerSite
Change listener for event DOMContentLoaded
Add site gmail
Change for-loop to method-call forEach
Add labels