Merge Chrome repo

Work on the Chrome version was started in an another repository as I
assumed there'd be little commonality between the Firefox and Chrome
versions. It's turned out otherwise.
Set xhr MIME type to quell Firefox "not-well formed" error
Ask users to support issue #13573
Bump version to 1.0.4
Update to suit manifest version 2

* Change background_page to background.page
* Change browser_action.popup to browser_action.default_popup
* Add web_accessible_resources so that icons can be displayed in notifications
* Update chrome.appeal.html so that it no longer has inline JavaScript
Remove redundant </div>
Bump Firefox maxVersion to 12.*
Remove Linux objects from install.rdf and manifest.json