Upgrade chrome extension manifest to version 2.

Change background.html to script.
Remove useless permissions.
Update to new message passing functions.
Look for both A and LINK elements, with either rel="bitcoin" or a bitcoin URL scheme href.

Parse bitcoin addresses to allow access to query options (e.g. label).
Show all found addresses in a popup box.
Also activate content script on https urls.
Change icons to bitcoin orange style.

Source: https://en.bitcoin.it/wiki/Promotional_graphics
All icons are based on the SVG, however icons below 48px have been customized for increased sharpness.
Move images to subdirectory.
Refine style sheet of popup box.
Add link to QR code image in popup.

Uses Google Chart API.
Merge pull request #1 from jonls/master

Update to chrome manifest version 2