Update piwik's javascript tracking code to the latest version.
Update piwik's async tracking code to the latest version.
Revert to older non-async piwik tracking code
Set use_async to be true.

Async tracking is now default for piwik. Set this to true so new installations use async tracking by default.
Update specs so that they pass with new code
Finish setting use_async as default
Add Image Tracking code
Add Piwik image tracker to non-async code
Don't have async as default.
Add some DRYness to this snippet and fix the tests as needed afterwards.
Bump version #
change async default back to false
Merge pull request #16 from illogic-al/master

Update Piwik tracking code to newest version

Thanks @illogic-al!