git-svn-id: http://dev.piwik.org/svn/trunk@7258 59fd770c-687e-43c8-a1e3-f5a4ff64c105

 * Adding Product page/Category page view tracking via Tracking function: setEcommerceView: function(sku, name, category)
This is using the Custom Variables per page, using slot 3/4/5 to track sku/name/category
 * UPdated PHP tracker + JS tracker + adding tests
 * Items reports (best SKU/Name/Category) will automatically call the Custom Vars API and enrich the items reports with "Visits", "Conversion rate"
 * Updating integration tests + fixing bug when item is deleted from Cart, then added again (or purchased)


git-svn-id: http://dev.piwik.org/svn/trunk@4723 59fd770c-687e-43c8-a1e3-f5a4ff64c105