Hide options while it's not working.
Fixed syntax error
Removed key
Hide option properly
Merge pull request #14 from dinhviethoa/11-fixed-syntax-error

Fixed syntax error in background.js
Merge pull request #13 from dinhviethoa/12-remove-key-manifest

Removed "key" from manifest.json
Merge pull request #15 from dinhviethoa/10-hide-options

Hide "options" while it's not working.